subject:(Physical chemistry)

University of Helsinki

1. Nikitin, Timur. Optical and structural properties of Si nanocrystals in SiO₂ film.

Degree: Department of Chemistry, Laboratory of Physical Chemistry, 2013, University of Helsinki

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Silicon nanocrystals (Si-nc) embedded in a SiO₂ matrix is a promising system for silicon-based photonics. We studied optical and structural properties of Si-rich silicon oxide… (more)

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Silicon nanocrystals (Si-nc) embedded in a SiO₂ matrix is a promising system for silicon-based photonics. We studied optical and structural properties of Si-rich silicon oxide SiOₓ (x < 2) films annealed in a furnace at temperatures up to 1200 °C and containing Si-nc. The measured optical properties of SiOₓ films are compared with the values estimated by using the effective medium approximation and X-ray photoelectron spectroscopy (XPS) results. A good agreement is found between the measured and calculated refractive index. The results for absorption suggest high transparency of nanoscale suboxide. The extinction coefficient for elemental Si is found to be between the values for crystalline and amorphous Si. Thermal annealing increases the degree of Si crystallization; however, the Si–SiO₂ phase separation is not complete after annealing at 1200 °C. The 1.5-eV photoluminescence probably originates from small (~1 nm) oxidized Si grains or oxygen-related defects, but not from Si-nc with sizes of about 4 nm. The SiOx films prepared by molecular beam deposition and ion implantation are structurally and optically very different after preparation but become similar after annealing at ~1100 °C. The laser-induced thermal effects found for SiOₓ films on silica substrates illuminated by focused laser light should be taken into account in optical measurements. Continuous-wave laser irradiation can produce very high temperatures in free-standing SiOₓ and Si/SiO₂ superlattice films, which changes their structure and optical properties. The center of a laser-annealed area is very transparent and consists of amorphous SiO₂. Large Si-nc (up to 300 nm) are observed in the ring around the central region. These Si-nc produce high absorption and they are typically under compressive stress, which is connected with the crystallization from the melt phase. Some of the large Si-nc exhibit surface features, which is interpreted in terms of eruption of pressurized Si from the film. A part of large Si-nc is removed from the film forming holes of similar sizes. The presence of oxygen in the laser-annealing atmosphere decreases the amount of removed Si-nc. The structure of laser-annealed areas is explained by thermodiffusion, which leads to the macroscopic Si–SiO₂ phase separation. Comparison of the structure of central regions for laser annealing in oxygen, air, and inert atmospheres excludes the dominating effect of Si oxidation in the formation of laser-annealed area. By using a strongly focused laser beam, the structural changes in the free-standing films can be obtained in submicron areas, which suggests a concept of nonvolatile optical memory with high information density and superior thermal stability.

Fotoniikan yhdistämisellä elektroniikkaan voidaan ratkaista monia modernien elektronisten laitteiden rajoittuneisuuksia. Piihin perustuva fotoniikka on erityisen lupaavaa, sillä pii on elektroniikan perusmateriaali. Yhdistämisessä haastavin tehtävä liittyy piihin perustuvan tehokkaan valolähteen konstruointiin. Piidioksidiin SiO₂…

Subjects/Keywords: physical Chemistry; physical Chemistry

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APA (6^th Edition):

Nikitin, T. (2013). Optical and structural properties of Si nanocrystals in SiO₂ film. (Doctoral Dissertation). University of Helsinki. Retrieved from http://hdl.handle.net/10138/41712

Chicago Manual of Style (16^th Edition):

Nikitin, Timur. “Optical and structural properties of Si nanocrystals in SiO₂ film.” 2013. Doctoral Dissertation, University of Helsinki. Accessed April 11, 2021. http://hdl.handle.net/10138/41712.

MLA Handbook (7^th Edition):

Nikitin, Timur. “Optical and structural properties of Si nanocrystals in SiO₂ film.” 2013. Web. 11 Apr 2021.

Vancouver:

Nikitin T. Optical and structural properties of Si nanocrystals in SiO₂ film. [Internet] [Doctoral dissertation]. University of Helsinki; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10138/41712.

Council of Science Editors:

Nikitin T. Optical and structural properties of Si nanocrystals in SiO₂ film. [Doctoral Dissertation]. University of Helsinki; 2013. Available from: http://hdl.handle.net/10138/41712

University of Helsinki

2. Chen, Wen. Generation mechanisms of hydrogen cyanide and ammonia in human exhaled breath.

Degree: Department of Chemistry, 2016, University of Helsinki

URL: http://hdl.handle.net/10138/168771

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Human exhaled breath contains hundreds of volatile compounds. Breath analysis is a method of seeking biomarkers among these volatiles, which could potentially serve as non-invasive… (more)

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Human exhaled breath contains hundreds of volatile compounds. Breath analysis is a method of seeking biomarkers among these volatiles, which could potentially serve as non-invasive medical indicators in disease diagnosis. With the development of analytical techniques more disease-related breath volatiles are being discovered. Exhaled hydrogen cyanide (HCN) and ammonia (NH3) have been studied previously. Both of them are potential biomarkers in clinical practice. Breath HCN has been proposed as a biomarker of Pseudomonas aeruginosa colonization in cystic fibrosis patients, since high levels of HCN are detected in the headspace of P. aeruginosa in vitro. Breath NH3 has been suggested as an indicator for monitoring hemodialysis (HD) adequacy in end-stage renal disease (ESRD) patients, since breath NH3 is strongly correlated to blood urea. To validate breath HCN and NH3 tests for clinical application, one has to understand the biochemical mechanisms of breath HCN and NH3 production in the human body. In some earlier studies, it was assumed that the oral cavity is a major production site for both breath HCN and NH3. However, the biochemical pathways of oral HCN and NH3 production have not been extensively studied. In this thesis, we investigated the correlation between salivary HCN and breath HCN in healthy subjects and confirmed that saliva is the main source for breath HCN. Additionally, we observed that oral anaerobes, including the genus of Porphyromonas, Prevotella and Fusobacterium, produce low levels of HCN in vitro. This implies that oral bacteria probably contribute to breath HCN generation. To explore the mechanism of breath NH3 production, we first conducted experiments on healthy subjects and found that salivary urea is the main source of breath NH3. We extended our study to ESRD patients during their HD treatment to investigate the connection between blood urea and breath NH3. Through the observation of strong correlations between blood urea, salivary urea, salivary ammonia and breath NH3, we were able to suggest a biochemical pathway for breath NH3 production. Blood urea is diffused into saliva through salivary glands. Salivary urea is subsequently hydrolysed into ammonia by urease activity. Finally, salivary ammonia evaporates into the gas phase and becomes breath NH3.

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Subjects/Keywords: physical chemistry; physical chemistry

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APA (6^th Edition):

Chen, W. (2016). Generation mechanisms of hydrogen cyanide and ammonia in human exhaled breath. (Doctoral Dissertation). University of Helsinki. Retrieved from http://hdl.handle.net/10138/168771

Chicago Manual of Style (16^th Edition):

Chen, Wen. “Generation mechanisms of hydrogen cyanide and ammonia in human exhaled breath.” 2016. Doctoral Dissertation, University of Helsinki. Accessed April 11, 2021. http://hdl.handle.net/10138/168771.

MLA Handbook (7^th Edition):

Chen, Wen. “Generation mechanisms of hydrogen cyanide and ammonia in human exhaled breath.” 2016. Web. 11 Apr 2021.

Vancouver:

Chen W. Generation mechanisms of hydrogen cyanide and ammonia in human exhaled breath. [Internet] [Doctoral dissertation]. University of Helsinki; 2016. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10138/168771.

Council of Science Editors:

Chen W. Generation mechanisms of hydrogen cyanide and ammonia in human exhaled breath. [Doctoral Dissertation]. University of Helsinki; 2016. Available from: http://hdl.handle.net/10138/168771

University of Helsinki

3. Zhu, Cheng. New noble-gas compounds and environmental effects.

Degree: Department of Chemistry, 2016, University of Helsinki

URL: http://hdl.handle.net/10138/160743

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Noble-gas chemistry was started in 1962 when Neil Bartlett reported the first noble-gas compound, xenon hexafluoroplatinate. This discovery was followed by successful synthesis of many… (more)

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Noble-gas chemistry was started in 1962 when Neil Bartlett reported the first noble-gas compound, xenon hexafluoroplatinate. This discovery was followed by successful synthesis of many other noble-gas compounds. Matrix-isolation infrared spectroscopy has been an important tool in noble-gas chemistry. In 1995, noble-gas hydrides HNgY (Ng is a noble-gas atom and Y is an electronegative fragment) were characterized by using this method. To date, a substantial number of noble-gas hydrides have been identified including the first neutral ground-state Ar compound, HArF. A few noble-gas compounds of the YNgY’ type (Y and Y’ are electronegative fragments) have also been prepared in matrices. This thesis consists of two parts. In the first part, two new HNgY compounds (HKrCCCl and HXeCCCl) and three new YNgY’ compounds (FKrCN, FXeCN, and FXeNC) are described. These molecules are prepared in noble-gas matrices (Kr and Xe) by ultraviolet photolysis of the precursors and subsequent annealing and characterized by infrared spectroscopy. The assignments are supported by ab initio calculations at the MP2(full) and CCSD(T) levels of theory. The precursors HCCCl and FCN are synthesized using a microwave discharge of HClC=CCl2/Ng and (FCN)3/Ng gaseous mixtures, respectively. The infrared spectrum of CCCl radical is also reported. In the second part, the complexation effect on HXeI and the matrix effect on HXeI and HXeH are studied. Two new complexes (HXeI···HCl and HXeI···HCCH) are prepared in a Xe matrix and assigned based on the ab initio calculations at the MP2(full) and CCSD(T) levels of theory. Similarly to the previously studied systems, the H–Xe stretching mode of HXeI in these complexes show substantial blue shifts. The decomposition of the HXeI complexes (including known HXeI···HBr and HXeI···HI) by broadband IR radiation of the spectrometer slows down as the H–Xe stretching frequency increases. HXeI and HXeH are studied in Ar, Kr, and Xe matrices. The order of the H–Xe stretching frequency of HXeH in these matrices (ν(Xe) < ν(Kr) < ν(Ar)) is the same as that of previously studied HXeCl, HXeBr, and HXeCCH. For HXeI, the frequency order is diffe rent: ν(Xe) < ν(Ar) < ν(Kr), which is a remarkable observation. The experimental results are successfully simulated using the hybrid quantum-classical calculations.

Subjects/Keywords: Physical Chemistry; Physical Chemistry

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APA (6^th Edition):

Zhu, C. (2016). New noble-gas compounds and environmental effects. (Doctoral Dissertation). University of Helsinki. Retrieved from http://hdl.handle.net/10138/160743

Chicago Manual of Style (16^th Edition):

Zhu, Cheng. “New noble-gas compounds and environmental effects.” 2016. Doctoral Dissertation, University of Helsinki. Accessed April 11, 2021. http://hdl.handle.net/10138/160743.

MLA Handbook (7^th Edition):

Zhu, Cheng. “New noble-gas compounds and environmental effects.” 2016. Web. 11 Apr 2021.

Vancouver:

Zhu C. New noble-gas compounds and environmental effects. [Internet] [Doctoral dissertation]. University of Helsinki; 2016. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10138/160743.

Council of Science Editors:

Zhu C. New noble-gas compounds and environmental effects. [Doctoral Dissertation]. University of Helsinki; 2016. Available from: http://hdl.handle.net/10138/160743

4. Patz, Carrie. Molecular level structure in water-alcohol mixtures; from shots to pints: L'Chaim!.

Degree: 2016, Iowa State University

URL: https://lib.dr.iastate.edu/etd/15066

► The two objectives of this work are to look at the molecular level mixing in water-alcohol liquid mixtures and to determine how well the Effective… (more)

Subjects/Keywords: Physical Chemistry; Physical Chemistry

2 more images…

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APA (6^th Edition):

Patz, C. (2016). Molecular level structure in water-alcohol mixtures; from shots to pints: L'Chaim!. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/15066

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Patz, Carrie. “Molecular level structure in water-alcohol mixtures; from shots to pints: L'Chaim!.” 2016. Thesis, Iowa State University. Accessed April 11, 2021. https://lib.dr.iastate.edu/etd/15066.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Patz, Carrie. “Molecular level structure in water-alcohol mixtures; from shots to pints: L'Chaim!.” 2016. Web. 11 Apr 2021.

Vancouver:

Patz C. Molecular level structure in water-alcohol mixtures; from shots to pints: L'Chaim!. [Internet] [Thesis]. Iowa State University; 2016. [cited 2021 Apr 11]. Available from: https://lib.dr.iastate.edu/etd/15066.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Patz C. Molecular level structure in water-alcohol mixtures; from shots to pints: L'Chaim!. [Thesis]. Iowa State University; 2016. Available from: https://lib.dr.iastate.edu/etd/15066

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

5. De Silva, Chamila Chandima. Computational study of boron binding environments and their role in some biological systems.

Degree: 2014, Iowa State University

URL: https://lib.dr.iastate.edu/etd/14151

► Boron, a fairly simple atom in the first row of periodic table, makes remarkable dative bonds, which have inspired the curiosity of researchers for decades.… (more)

▼ Boron, a fairly simple atom in the first row of periodic table, makes remarkable dative bonds, which have inspired the curiosity of researchers for decades. Boron has three valence electrons and when in compounds the boron atom is often sp2 hybridized and has a planar structure. An empty p-orbital, which has the capability of accepting an electron pair, makes boron a good Lewis acid and once the lone pair is gained the structure around the boron becomes tetrahedral. While Boron-Nitrogen, B-N dative bonds have been extensively studied throughout the years, other boron dative bonds such as B-O and B-P also have shown remarkable characteristics. Boron-Nitrogen containing compounds such as ammonia borane, metal amidoboranes, and organoboron boron compounds have shown to be promising hydrogen storage materials. These compounds release hydrogen upon heating, which, can be used as a clean energy source. Thermolysis of amino-boron compounds is an exothermic process. Once the initial hydrogen is released it will gives out enough energy for a self-sustained hydrogen release. But this ongoing exothermic reactions increase the temperature of the system and can even cause breaking of boron-nitrogen bond, forming low molecular weight byproducts such as borone, ammonia and borozine, that can pollute the proton exchange membrane fuel cells (PEM fuel cells). This type of technological utility adds to the interest in carrying out studies to understand the B-N bond energies of different boron nitrogen compounds. Knowing the dissociation bond energies for B-N is useful in controlling the reaction temperatures of thermolysis process. Boron neutron capture therapy (BNCT) is a powerful form of radiotherapy, which incorporate 10B-containing compounds into tumor cells, followed by the irradiation of tumor/cancer cells with thermal neutrons. Subsequent to absorbing the neutron, the resulting 11B is unstable and decays into Li and 4He, a high-energy reaction, which destroys tumor cells without damaging as many of the surrounding healthy cells as other forms of chemotherapy. The most important requirement for the boron neutron-capture therapy is the high and selective accumulation of boron in tumor cells, where the boron-containing molecule should adhere to both boron and to the targeted cancer cell. Finding boron compounds with high selectivity, water solubility and low toxicity in high concentrations is a major problem in the advancement of treatment using BNCT. Therefore studying of boron binding environments is essential in the field of radiotherapy. Phosphorous, which plays an important role in human body as phosphates is a good example of selective boron binding for treatment of cancer cells. In addition to its part as an essential building block in DNA and RNA and as an energy transporter in the form of nucleoside di- and triphosphate, it contributes strongly to the strength and integrity of the bone skeleton. Bisphosphonates, used as a treatment for diseases like osteoporosis and rheumatoid arthritis, can be strongly adsorbed to…

Subjects/Keywords: Physical Chemistry; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

De Silva, C. C. (2014). Computational study of boron binding environments and their role in some biological systems. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/14151

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

De Silva, Chamila Chandima. “Computational study of boron binding environments and their role in some biological systems.” 2014. Thesis, Iowa State University. Accessed April 11, 2021. https://lib.dr.iastate.edu/etd/14151.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

De Silva, Chamila Chandima. “Computational study of boron binding environments and their role in some biological systems.” 2014. Web. 11 Apr 2021.

Vancouver:

De Silva CC. Computational study of boron binding environments and their role in some biological systems. [Internet] [Thesis]. Iowa State University; 2014. [cited 2021 Apr 11]. Available from: https://lib.dr.iastate.edu/etd/14151.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

De Silva CC. Computational study of boron binding environments and their role in some biological systems. [Thesis]. Iowa State University; 2014. Available from: https://lib.dr.iastate.edu/etd/14151

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Wright State University

6. Jordan, Carly A. Work Function Modification of Metal Electrodes via Printing of PEDOT:PSS and Carbon Nanotubes.

Degree: MS, Chemistry, 2015, Wright State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=wright1440696711

► Work function tunability of metal electrodes provides a route to improving performance of organic electronic devices. Using an electrode with a different work function changes… (more)

Subjects/Keywords: Physical Chemistry; physical chemistry

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APA (6^th Edition):

Jordan, C. A. (2015). Work Function Modification of Metal Electrodes via Printing of PEDOT:PSS and Carbon Nanotubes. (Masters Thesis). Wright State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=wright1440696711

Chicago Manual of Style (16^th Edition):

Jordan, Carly A. “Work Function Modification of Metal Electrodes via Printing of PEDOT:PSS and Carbon Nanotubes.” 2015. Masters Thesis, Wright State University. Accessed April 11, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1440696711.

MLA Handbook (7^th Edition):

Jordan, Carly A. “Work Function Modification of Metal Electrodes via Printing of PEDOT:PSS and Carbon Nanotubes.” 2015. Web. 11 Apr 2021.

Vancouver:

Jordan CA. Work Function Modification of Metal Electrodes via Printing of PEDOT:PSS and Carbon Nanotubes. [Internet] [Masters thesis]. Wright State University; 2015. [cited 2021 Apr 11]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=wright1440696711.

Council of Science Editors:

Jordan CA. Work Function Modification of Metal Electrodes via Printing of PEDOT:PSS and Carbon Nanotubes. [Masters Thesis]. Wright State University; 2015. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=wright1440696711

Princeton University

7. Gontijo Campos, Andre. Quantum Control over Vast Time Scales and Length Scales.

Degree: 2017, Princeton University

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10619678

► Quantum control theory (QCT) is concerned with the active manipulation of phys- ical and chemical processes on the atomic and molecular scale. For a… (more)

▼ Quantum control theory (QCT) is concerned with the active manipulation of phys- ical and chemical processes on the atomic and molecular scale. For a specified con- trol objective, and with restrictions imposed by many possible constraints, the time- dependent field required to manipulate the system in a desired way can be designed using quantum control theory. This dissertation proposes several novel applications of QCT to actively manipulate the dynamics of both quantum and classical systems with and without interactions with an external environment, in both relativistic and non-relativistic regimes. In Chapter 2, the paradigm of spectral dynamic mimicry (SDM) in which laser fields are shaped to make any atomic and molecular systems look identical spectrally is put forward. SDM successfully avoids optimization rou- tines, and provides a powerful tool to find a laser pulse that induces a desired optical response from an arbitrary dynamical system. As illustrations, driving fields are com- puted to induce the same optical response from a variety of distinct systems (open and closed, quantum and classical). The formulation may also be applied to design materials with specified optical characteristics. These findings reveal unexplored flex- ibilities of nonlinear optics. Little is known about the control of relativistic quantum systems. Therefore, an extension of QCT to the Dirac equation is proposed. The main contributions are: (i) Chapters 3 and 4 reach an unprecedented level of control while providing exciting new insights on the complex quantum dynamics of relativis- tic electrons. The method developed provides a very powerful tool to generate new analytical solutions to the Dirac equation, (ii) Chapters 5 and 6 present an open system interaction formalism for the Dirac equation. The presented framework en- ables efficient numerical simulations of relativistic dynamics within the von Neumann density matrix and Wigner phase space descriptions, an essential requirement for the application of QCT, (iii) Chapter 7 proposes a Lindblad model of quantum elec- trodynamics (QED). The presented formalism enables a very efficient and practical numerical method to simulate QED effects, such as the Lamb shift and the anomalous magnetic moment of the electron, for a broad variety of systems.

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Gontijo Campos, A. (2017). Quantum Control over Vast Time Scales and Length Scales. (Thesis). Princeton University. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10619678

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gontijo Campos, Andre. “Quantum Control over Vast Time Scales and Length Scales.” 2017. Thesis, Princeton University. Accessed April 11, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10619678.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gontijo Campos, Andre. “Quantum Control over Vast Time Scales and Length Scales.” 2017. Web. 11 Apr 2021.

Vancouver:

Gontijo Campos A. Quantum Control over Vast Time Scales and Length Scales. [Internet] [Thesis]. Princeton University; 2017. [cited 2021 Apr 11]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10619678.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gontijo Campos A. Quantum Control over Vast Time Scales and Length Scales. [Thesis]. Princeton University; 2017. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10619678

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

8. Smith, Jacob W. Investigating Ion Solvation in Electrolyte Solutions via X-ray Absorption Spectroscopy.

Degree: Chemistry, 2016, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/84c0k8k2

► X-ray Absorption Spectroscopy (XAS) is a powerful atom-selective probe of the local chemical environment of a target atom. Streaming liquid microjets, created by forcing liquid… (more)

▼ X-ray Absorption Spectroscopy (XAS) is a powerful atom-selective probe of the local chemical environment of a target atom. Streaming liquid microjets, created by forcing liquid at high pressures (ca. 20-100 atm.) through a capillary tube of inner diameter 30-100 µm, allow for liquids to be introduced into a vacuum chamber and interrogated with soft X-rays generated by synchrotron light sources. This technique has enabled the study of many liquids and solutions. In this dissertation, the use of soft X-ray XAS for the study of the solvation of ions in electrolyte solutions is discussed. The majority of chemical reactions occur in the solution phase. The thermodynamics and kinetics of these reactions are explicitly dependent upon the local chemical environments of the reactants. Consequently, knowledge of the solvation of ions in solution is critical to understanding their chemistry in this phase. By interpreting XAS measurements with ab initio Density Functional Theory (DFT)-based electronic structure calculations, it is possible to acquire valuable knowledge about the local chemical environment of ions and molecules in solution, such as the solvation number and geometry and propensity to form ion pairs. Commercial lithium ion batteries typically contain a liquid electrolyte comprising a lithium salt dissolved in a mixture of alkyl carbonates such as propylene carbonate, dimethyl carbonate, and ethylene carbonate. The solvation environment of the lithium ion in these solutions is thought to direct the formation of the Solid Electrolyte Interphase (SEI), which in turn is believed to play a critical role in determining essential cell properties including power output, recharging rate, and cycle life. Consequently, understanding this solvation environment is of critical importance. Here I report the a study of the solvation of Li+ in solutions of LiBF4 in alkyl carbonates via XAS on the carbon and oxygen K-edges. In collaboration with Dr. David Prendergast, we have performed electronic structure calculations within the eXcited electron and Core Hole (XCH) approximation and extracted a solvation number for Li+ in propylene carbonate. I also report the study of aqueous solutions sodium nitrate and nitrite on the nitrogen K-edge utilizing similar experimental and theoretical methods. Aqueous nitrate and nitrite salts are important commercial reagents and play a critical role in the global nitrogen cycle. A detailed understanding of their chemical environment of solution would be beneficial in understanding and modeling reactivity. Unfortunately, the nitrogen K-edge XAS spectra of these species are found to be largely insensitive to ion pairing and solvation geometry around the anion, such that limited chemical information was extracted from this study.

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Smith, J. W. (2016). Investigating Ion Solvation in Electrolyte Solutions via X-ray Absorption Spectroscopy. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/84c0k8k2

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Smith, Jacob W. “Investigating Ion Solvation in Electrolyte Solutions via X-ray Absorption Spectroscopy.” 2016. Thesis, University of California – Berkeley. Accessed April 11, 2021. http://www.escholarship.org/uc/item/84c0k8k2.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Smith, Jacob W. “Investigating Ion Solvation in Electrolyte Solutions via X-ray Absorption Spectroscopy.” 2016. Web. 11 Apr 2021.

Vancouver:

Smith JW. Investigating Ion Solvation in Electrolyte Solutions via X-ray Absorption Spectroscopy. [Internet] [Thesis]. University of California – Berkeley; 2016. [cited 2021 Apr 11]. Available from: http://www.escholarship.org/uc/item/84c0k8k2.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Smith JW. Investigating Ion Solvation in Electrolyte Solutions via X-ray Absorption Spectroscopy. [Thesis]. University of California – Berkeley; 2016. Available from: http://www.escholarship.org/uc/item/84c0k8k2

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Santa Cruz

9. Liu, Ke. Nanostructured Materials as Effective Catalysts for Oxygen Reduction Reactions (ORR).

Degree: Chemistry, 2015, University of California – Santa Cruz

URL: http://www.escholarship.org/uc/item/8pj4n36f

► Fuel cells are clean and efficient power sources which can convert chemical energy of hydrogen and oxygen into electricity. The Gibbs free energy of hydrogen… (more)

▼ Fuel cells are clean and efficient power sources which can convert chemical energy of hydrogen and oxygen into electricity. The Gibbs free energy of hydrogen fuel cells can be as high as -273.13 kJ mol-1, and the theoretical energy conversion efficiency is high as well. However, the cathode oxygen reduction reaction (so-called ORR reaction) is kinetically slow and regarded as bottleneck of fuel cell technology. Thus extensive efforts have been spent on developing efficient catalysts where oxygen molecules can be reduced to water efficient and fast. In this thesis, the research efforts are focused on developing various nanostructured materials as efficient ORR catalysts. In detail, the research mainly focuses on two directions: first, develop Pt-based ORR catalysts with improved ORR activities compared to commercial Pt/C catalysts; second, develop non-precious but highly-efficient ORR catalysts.Commercial Pt/C catalysts are one of the best ORR catalysts due to their good balance of activities and stabilities. However, the price of Pt is high and its reserve is limited, thus efforts should be spent in improving specific activity of Pt-based ORR catalysts aiming to decrease usage of Pt and the cost on catalysts. Recently it’s reported that deliberate manipulation chemical functionalization of metal nanoparticles can significantly increase their electrocatalytic activities. Inspired by those work, acetylene derivatives were adopted to functionalize surface of Pt nanoparticles in the first project, in order to explore different metal-ligand interfacial bonding interactions on the nanoparticle electrocatalytic activity. It’s revealed that specific activity of Pt nanoparticles after ligand functionalization was all markedly better than that of commercial Pt/C catalysts, which was accounted for by the deliberate manipulation of the electronic structure of the Pt nanoparticles.Besides organic ligand functionalization, graphene-based materials were reported capable of decreasing surface electron density of Pt, which is believed beneficial for the electrocatalytic activity. In the second project, Pt nanoparticles were deposited on graphene quantum dots, a relatively new member of graphene-based materials, producing Pt/GQD composite as evidenced by TEM and XRD measurements. In comparison with commercial Pt/C catalysts, the Pt/GQD composite showed markedly enhanced catalytic activity in oxygen reduction reaction, with an onset potential 70 mV more positive than that of Pt/C, a specific activity that was almost nine times higher, and excellent long-term stability.Although it’s proven effective to improve ORR activity of Pt-based materials by ligand functionalization and introducing interactions between graphene quantum dots, the high price of Pt still drives efforts spent in developing non-precious efficient ORR catalysts. Compared with Pt, copper is inexpensive candidate materials with good conductivity, and polycrystalline copper electrode is reported to exhibit apparent electrocatalytic activity in oxygen reduction reaction.…

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Liu, K. (2015). Nanostructured Materials as Effective Catalysts for Oxygen Reduction Reactions (ORR). (Thesis). University of California – Santa Cruz. Retrieved from http://www.escholarship.org/uc/item/8pj4n36f

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liu, Ke. “Nanostructured Materials as Effective Catalysts for Oxygen Reduction Reactions (ORR).” 2015. Thesis, University of California – Santa Cruz. Accessed April 11, 2021. http://www.escholarship.org/uc/item/8pj4n36f.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liu, Ke. “Nanostructured Materials as Effective Catalysts for Oxygen Reduction Reactions (ORR).” 2015. Web. 11 Apr 2021.

Vancouver:

Liu K. Nanostructured Materials as Effective Catalysts for Oxygen Reduction Reactions (ORR). [Internet] [Thesis]. University of California – Santa Cruz; 2015. [cited 2021 Apr 11]. Available from: http://www.escholarship.org/uc/item/8pj4n36f.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liu K. Nanostructured Materials as Effective Catalysts for Oxygen Reduction Reactions (ORR). [Thesis]. University of California – Santa Cruz; 2015. Available from: http://www.escholarship.org/uc/item/8pj4n36f

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

10. Thirman, Jonathan E. A Second-Order Møller–Plesset Perturbation Theory Energy Decomposition Analysis for Intermolecular Interactions: Design, Implementation, and Application.

Degree: Chemistry, 2017, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/6156f7mm

► This thesis is concerned with the development an analysis for decomposing the binding energy of second-order Møller–Plesset perturbation theory into physically meaningful components. This can… (more)

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Thirman, J. E. (2017). A Second-Order Møller–Plesset Perturbation Theory Energy Decomposition Analysis for Intermolecular Interactions: Design, Implementation, and Application. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/6156f7mm

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Thirman, Jonathan E. “A Second-Order Møller–Plesset Perturbation Theory Energy Decomposition Analysis for Intermolecular Interactions: Design, Implementation, and Application.” 2017. Thesis, University of California – Berkeley. Accessed April 11, 2021. http://www.escholarship.org/uc/item/6156f7mm.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Thirman, Jonathan E. “A Second-Order Møller–Plesset Perturbation Theory Energy Decomposition Analysis for Intermolecular Interactions: Design, Implementation, and Application.” 2017. Web. 11 Apr 2021.

Vancouver:

Thirman JE. A Second-Order Møller–Plesset Perturbation Theory Energy Decomposition Analysis for Intermolecular Interactions: Design, Implementation, and Application. [Internet] [Thesis]. University of California – Berkeley; 2017. [cited 2021 Apr 11]. Available from: http://www.escholarship.org/uc/item/6156f7mm.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Thirman JE. A Second-Order Møller–Plesset Perturbation Theory Energy Decomposition Analysis for Intermolecular Interactions: Design, Implementation, and Application. [Thesis]. University of California – Berkeley; 2017. Available from: http://www.escholarship.org/uc/item/6156f7mm

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

11. Thomas, John Christopher. Probing Buried and Exposed Interfaces with Submolecular Precision.

Degree: Chemistry, 2015, UCLA

URL: http://www.escholarship.org/uc/item/13f651m2

► The chemistry of nanoscale materials and self-assembled monolayers are largely determined by interfacial properties, structural dimensionality, bonding and lattice structures, and defect types and densities.… (more)

▼ The chemistry of nanoscale materials and self-assembled monolayers are largely determined by interfacial properties, structural dimensionality, bonding and lattice structures, and defect types and densities. Bottom-up design strategies differ from prototypical top-down nanofabrication approaches in that the aim is to control and to place single molecules and atoms precisely, which may provide routes to breaking the current lithography limits. Scanning tunneling microscopy (STM) is able to probe the molecular world and to extract information from single molecules, groups of molecules, and even submolecular features. Here, we use STM in both ultrastable and ambient conditions to test the nature of dipolar interactions between molecules, to probe novelbuilding blocks for assembly, to manipulate surface binding modes, to examine a holey graphene framework against chemical deposition as a means in patterning, and to explore the nature of buried hydrogen-bonding networks in self-assembled monolayer matrices. The simultaneous usage of STM in topographic imaging mode and local barrier height (LBH) mode, in an ultrahigh vacuum (≤10-12 torr) and low temperature (4 K) environment, enables the measurement of both molecular topography and the buried dipolar interface. Using a block-matching approach, the correlation between molecular apexes and dipolar extrema is computed, thus enabling the visualization of molecular orientations at the submolecular scale. We also use STM in ambient conditions to examine the assembly of p-mercaptobenzoic acid derivative of carboranethiol on a Au{111} surface, where the carboxyl-modified carboranethiol backbone provides a surface available for further chemical functionality. Adding a second thiol group attachment in 1,2-carboranedithiol and 9,12-carboranedithiol isomers enables the control of valency between neighboring thiol/thiolate attachment sites. The assembly and manipulation of the two different binding modes using simple acid-base chemistry is evaluated and measured at a local level. Two-dimensional graphene has garnered much interest recently due to extraordinary two-dimensional properties. The design and placement of holes within a protecting sheet is tested against the deposition of molecules, where the holey network acts as a mask that may find use in lithographic processing. Hydrogen bonds also exhibit strong dipoles, where STM in simultaneous topographic and LBH mode may be able to measure the topographic map along with buried amide bond dipoles. We use an amide-containing self-assembled network to evaluate the nature of these ‘hidden’ networks at the single-molecule scale. The embodiment of this work aims to provide a fundamental understanding of chemical properties at the nanoscale and a complementary tool with averaging and ensemble techniques.

Subjects/Keywords: Chemistry; Physical chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Thomas, J. C. (2015). Probing Buried and Exposed Interfaces with Submolecular Precision. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/13f651m2

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Thomas, John Christopher. “Probing Buried and Exposed Interfaces with Submolecular Precision.” 2015. Thesis, UCLA. Accessed April 11, 2021. http://www.escholarship.org/uc/item/13f651m2.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Thomas, John Christopher. “Probing Buried and Exposed Interfaces with Submolecular Precision.” 2015. Web. 11 Apr 2021.

Vancouver:

Thomas JC. Probing Buried and Exposed Interfaces with Submolecular Precision. [Internet] [Thesis]. UCLA; 2015. [cited 2021 Apr 11]. Available from: http://www.escholarship.org/uc/item/13f651m2.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Thomas JC. Probing Buried and Exposed Interfaces with Submolecular Precision. [Thesis]. UCLA; 2015. Available from: http://www.escholarship.org/uc/item/13f651m2

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

12. Zhang, Guangye. Study of Device Physics and Active Layer Morphology in Polymer-Fullerene Based Solar Cells: The Role of Vertical Phase Segregation and Organic/Metal Interface.

Degree: Chemistry, 2015, UCLA

URL: http://www.escholarship.org/uc/item/4gr4v15g

► Organic photovoltaics (OPVs) are flexible, low cost and easily processable, which provides them with a very short energy payback time compared to most PV technologies… (more)

▼ Organic photovoltaics (OPVs) are flexible, low cost and easily processable, which provides them with a very short energy payback time compared to most PV technologies and makes them strong candidates for industrial mass production. The richness of organic synthesis has afforded a large library of molecular semiconductors, among which the combination of conjugated polymers as electron donors and fullerenes as electron acceptors has been demonstrated to be the best sellers as building blocks of OPV devices. In the past few years, the majority of research focus on OPVs has been devoted to improving their power conversion efficiencies by using new combinations of polymer and fullerene materials. Most devices are based on blend-cast bulk heterojunctions (BHJs), in which a polymer and fullerene are mixed together in a solution that is then used to cast the active layer of the organic solar cell. Because the nm-scale morphology of the film depends on so many of the details of how it is cast, the device performance of blend-cast BHJ solar cells is hypersensitive to the processing kinetics of the active layer. Thus, for any new set of OPV materials, an Edisonian approach involving the fabrication of hundreds of blend-cast devices is needed to find the processing conditions that lead to the optimal morphology and best device performance. In this thesis, I will focus on two main contributions that I have made to help rationally design OPVs.First, our group recently has gone beyond the traditional method of simply blending the donor and acceptor material by developing a new technique to process the active layer of OPVs called sequential processing. This method takes advantage of a pair of quasi-orthogonal solvents to process the two components used in the active layer separately. By studying a series of crystalline polymers with controlled regioregularities and polydispersities, I have found that increasing polymer crystallinity produces the opposite behavior in BHJ solar cells fabricated by sequentially-processing and blend-casting. This suggests that the two processing techniques are complementary and provides guidance on selecting the appropriate processing technique for a given polymer. Second, I have studied the performance and device physics of a new series of controllably tuned fullerene derivatives applied in traditional blend-cast active layers. We obtained a series of carefully designed 1,4-dibenzyl fullerene bisadducts synthesized by our collaborators in Prof. Yves Rubin's group. The fullerenes have methoxy substituents selectively positioned on pendant phenyl rings, which allows us to examine the effect of the subtle molecular changes on both macroscopic solar cell performance and the underlying device physics. Through carrier recombination studies, I have learned that solar cell performance often depends on the material's surface energy and the vertical phase segregation caused by this surface energy in the active layer. The results will allow us to offer new directions on how to select the best device…

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Zhang, G. (2015). Study of Device Physics and Active Layer Morphology in Polymer-Fullerene Based Solar Cells: The Role of Vertical Phase Segregation and Organic/Metal Interface. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/4gr4v15g

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Guangye. “Study of Device Physics and Active Layer Morphology in Polymer-Fullerene Based Solar Cells: The Role of Vertical Phase Segregation and Organic/Metal Interface.” 2015. Thesis, UCLA. Accessed April 11, 2021. http://www.escholarship.org/uc/item/4gr4v15g.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Guangye. “Study of Device Physics and Active Layer Morphology in Polymer-Fullerene Based Solar Cells: The Role of Vertical Phase Segregation and Organic/Metal Interface.” 2015. Web. 11 Apr 2021.

Vancouver:

Zhang G. Study of Device Physics and Active Layer Morphology in Polymer-Fullerene Based Solar Cells: The Role of Vertical Phase Segregation and Organic/Metal Interface. [Internet] [Thesis]. UCLA; 2015. [cited 2021 Apr 11]. Available from: http://www.escholarship.org/uc/item/4gr4v15g.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang G. Study of Device Physics and Active Layer Morphology in Polymer-Fullerene Based Solar Cells: The Role of Vertical Phase Segregation and Organic/Metal Interface. [Thesis]. UCLA; 2015. Available from: http://www.escholarship.org/uc/item/4gr4v15g

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Irvine

13. Yampolsky, Steven Eugene. Tomographic State Reconstruction and Time Resolved Surface Enhanced Coherent Anti-Stokes Raman Scattering in the Single Molecule Limit.

Degree: Chemistry, 2014, University of California – Irvine

URL: http://www.escholarship.org/uc/item/2d97w3tt

► Time-resolved, surface-enhanced, coherent anti-Stokes Raman spectroscopy (tr-SECARS) isideally suited for preparing and probing vibrational coherences in molecules. By enhancingthe local response of a single molecule… (more)

▼ Time-resolved, surface-enhanced, coherent anti-Stokes Raman spectroscopy (tr-SECARS) isideally suited for preparing and probing vibrational coherences in molecules. By enhancingthe local response of a single molecule with a dipolar nano-antenna, vibrational dynamicshave been measured at the single molecule limit. In contrast with tr-CARS measurementsin ensembles, the vibrational coherence of a single molecule is not subject to pure dephasing.It exhibits characteristic phase and amplitude noise, which allows the statistical distinctionbetween single, few, and many molecule sources to be determined. To build on the cur-rent work, by using three unique pulses to spectrally lter the response of the molecule,the characteristic noise can be isolated and measured background-free. If the probing of asuperposition state is carried out over a real resonance, then it is possible to tomographicallyreconstruct the complete description of quantum dynamics in phase space representation viathe Wigner Distribution Function(WDF). The WDF can be reconstructed from either thewavepacket via Wigner Transform, or an experimentally measured density, via an InverseRadon Transform. The calculations presented here highlight the necessary conditions inorder to reconstruct the WDF with delity from a proposed experiment and compare thedensity derived WDF with that of the wavepacket. The principle is rstly demonstrated us-ing a Kerr gated detection of emission from an evolving state on a bound harmonic potentialenergy surface. The model is then explained in the case of a proposed spectrally resolvedtransient grating experiment (SRTG). The WDFs generated from the limiting conditionsshow that the reproduction delity of the experimentally derived WDF are dependent onthe probe, utilized to measure the evolving superposition, and the curvature, or the vibra-tional frequency of the potential energy surfaces, and the dephasing time of the vibrationalsuperposition states. Given two potentials, I show that it is possible to optimize probepulse parameters to improve the delity of the state reconstruction. Due to the variationalprinciple, the negative volume of the WDF, or the Wigner hole, can only be reduced viameasurements - the pulse parameters can be optimized iteratively even when the molecularpotentials are not known.

Subjects/Keywords: Physical chemistry; Chemistry

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APA (6^th Edition):

Yampolsky, S. E. (2014). Tomographic State Reconstruction and Time Resolved Surface Enhanced Coherent Anti-Stokes Raman Scattering in the Single Molecule Limit. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/2d97w3tt

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Yampolsky, Steven Eugene. “Tomographic State Reconstruction and Time Resolved Surface Enhanced Coherent Anti-Stokes Raman Scattering in the Single Molecule Limit.” 2014. Thesis, University of California – Irvine. Accessed April 11, 2021. http://www.escholarship.org/uc/item/2d97w3tt.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Yampolsky, Steven Eugene. “Tomographic State Reconstruction and Time Resolved Surface Enhanced Coherent Anti-Stokes Raman Scattering in the Single Molecule Limit.” 2014. Web. 11 Apr 2021.

Vancouver:

Yampolsky SE. Tomographic State Reconstruction and Time Resolved Surface Enhanced Coherent Anti-Stokes Raman Scattering in the Single Molecule Limit. [Internet] [Thesis]. University of California – Irvine; 2014. [cited 2021 Apr 11]. Available from: http://www.escholarship.org/uc/item/2d97w3tt.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Yampolsky SE. Tomographic State Reconstruction and Time Resolved Surface Enhanced Coherent Anti-Stokes Raman Scattering in the Single Molecule Limit. [Thesis]. University of California – Irvine; 2014. Available from: http://www.escholarship.org/uc/item/2d97w3tt

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Lueckheide, Michael James. On the Structure-Property Relationships of Oligonucleotide Polyelectrolyte Complexes and Complex Micelles.

Degree: 2019, The University of Chicago

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10978422

► Oligonucleotides, short nucleic acids of ≈ 100 bases and under, are therapeutics of great interest because of their ability to regulate gene expression and… (more)

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Lueckheide, M. J. (2019). On the Structure-Property Relationships of Oligonucleotide Polyelectrolyte Complexes and Complex Micelles. (Thesis). The University of Chicago. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10978422

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lueckheide, Michael James. “On the Structure-Property Relationships of Oligonucleotide Polyelectrolyte Complexes and Complex Micelles.” 2019. Thesis, The University of Chicago. Accessed April 11, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10978422.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lueckheide, Michael James. “On the Structure-Property Relationships of Oligonucleotide Polyelectrolyte Complexes and Complex Micelles.” 2019. Web. 11 Apr 2021.

Vancouver:

Lueckheide MJ. On the Structure-Property Relationships of Oligonucleotide Polyelectrolyte Complexes and Complex Micelles. [Internet] [Thesis]. The University of Chicago; 2019. [cited 2021 Apr 11]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10978422.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lueckheide MJ. On the Structure-Property Relationships of Oligonucleotide Polyelectrolyte Complexes and Complex Micelles. [Thesis]. The University of Chicago; 2019. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10978422

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Temple University

15. Tuladhar, Aashish. Structure and Dynamics of Water Next to Mineral Surfaces.

Degree: PhD, 2016, Temple University

URL: http://digital.library.temple.edu/u?/p245801coll10,420679

►

Chemistry

Vibrational sum frequency generation (vSFG) spectroscopy is a second order non-linear technique that can efficiently and selectively investigate an interface between two media. vSFG… (more)

▼

Chemistry

Vibrational sum frequency generation (vSFG) spectroscopy is a second order non-linear technique that can efficiently and selectively investigate an interface between two media. vSFG spectroscopy has been frequently used to interrogate the mineral/water interface by probing the interfacial O−H stretch, which is an excellent reporter of its hydrogen bonding environment. My work, described in this dissertation, is focused on using steady-state and time-resolved vSFG spectroscopy to understand how (a) the type of mineral, (b) the crystalline faces of the mineral, (c) the surface charge of the mineral, and (d) the ionic strength of the bulk liquid affect the structure and the ultrafast dynamics of the mineral/water interface. The results obtained for alumina/water interface are compared with the more commonly studied silica/water interface. The Al2O3/H2O interface provides an ideal opportunity to study the behavior of water next to a positively charged, neutral, and negatively charged mineral surface since its point of zero charge (PZC) lies near the pH of neutral water (pH 6-8). In contrast, due to its low PZC (~pH 2), silica surface is usually neutral or negatively charged. Additionally, a-alumina is crystalline in structure and can be cut to expose different faces (e.g., 0001, 11 ̅02, 112 ̅0) which has been speculated to uniquely affect the ordering and the hydrogen bonding environment of its adjacent water molecules. Our vSFG spectra of the O-H stretch at the alumina/water interface revealed the presence of highly red-shifted 3000 cm-1 species, which is absent at the silica/water interface. With the help of DFT calculations, we assigned the red-shifted peak to the O-H stretch of strongly hydrogen bonded surface aluminol groups and/or interfacial water molecules that are hydrogen bonded to the mineral surface. The 3000 cm-1 species was present at both the Al2O3(0001) and the Al2O3(112 ̅0) surface, but was more prominent for the latter which resulted in the O-H stretch of the Al2O3(112 ̅0)/H2O interface to appear more red-shifted compared to the Al2O3(0001)/H2O interface. This observation provided us with an experimental evidence that the water next to the Al2O3(112 ̅0) surface is in a stronger hydrogen bonded environment than next to the Al2O3(0001) surface as predicted by Catalano’s X-ray reflectivity measurements. Additionally, IR pump - vSFG probe experiments were used to investigate the ultrafast vibrational dynamics of the O-H stretch at alumina/water interfaces. The vibrational dynamics at the Al2O3(112 ̅0)/H2O interface was observed to be fast (T1 = 100-130 fs) and not affected by the mineral surface charge (controlled by bulk pH) or the ionic strength (up to 0.5 M NaCl). In contrast, for the Al2O3(0001)/H2O interface, the vibrational dynamics was observed to be two times faster for the charged surface (T1 ~ 105 fs) compared to the neutral surface (T1 ~ 220 fs). This result provides further evidence that the water next to the Al2O3(112 ̅0) surface is more ordered and/or strongly hydrogen bonded…

Advisors/Committee Members: Borguet, Eric;, Levis, Robert J., Voelz, Vincent, Yeganeh, Mohsen S.;.

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Tuladhar, A. (2016). Structure and Dynamics of Water Next to Mineral Surfaces. (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,420679

Chicago Manual of Style (16^th Edition):

Tuladhar, Aashish. “Structure and Dynamics of Water Next to Mineral Surfaces.” 2016. Doctoral Dissertation, Temple University. Accessed April 11, 2021. http://digital.library.temple.edu/u?/p245801coll10,420679.

MLA Handbook (7^th Edition):

Tuladhar, Aashish. “Structure and Dynamics of Water Next to Mineral Surfaces.” 2016. Web. 11 Apr 2021.

Vancouver:

Tuladhar A. Structure and Dynamics of Water Next to Mineral Surfaces. [Internet] [Doctoral dissertation]. Temple University; 2016. [cited 2021 Apr 11]. Available from: http://digital.library.temple.edu/u?/p245801coll10,420679.

Council of Science Editors:

Tuladhar A. Structure and Dynamics of Water Next to Mineral Surfaces. [Doctoral Dissertation]. Temple University; 2016. Available from: http://digital.library.temple.edu/u?/p245801coll10,420679

University of California, Riverside

16. Caulkins, Bethany Gayle. Enzymatic Intermediates of Tryptophan Synthase at Atomic Resolution Using Solid-State NMR.

Degree: 2017, University of California, Riverside

URL: http://pqdtopen.proquest.com/#viewpdf?dispub=10286555

► The acid-base chemistry that drives catalysis in pyridoxal-5'-phosphate (PLP)-dependent enzymes has been the subject of intense interest and investigation since the initial identification of… (more)

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

Caulkins, B. G. (2017). Enzymatic Intermediates of Tryptophan Synthase at Atomic Resolution Using Solid-State NMR. (Thesis). University of California, Riverside. Retrieved from http://pqdtopen.proquest.com/#viewpdf?dispub=10286555

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Caulkins, Bethany Gayle. “Enzymatic Intermediates of Tryptophan Synthase at Atomic Resolution Using Solid-State NMR.” 2017. Thesis, University of California, Riverside. Accessed April 11, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=10286555.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Caulkins, Bethany Gayle. “Enzymatic Intermediates of Tryptophan Synthase at Atomic Resolution Using Solid-State NMR.” 2017. Web. 11 Apr 2021.

Vancouver:

Caulkins BG. Enzymatic Intermediates of Tryptophan Synthase at Atomic Resolution Using Solid-State NMR. [Internet] [Thesis]. University of California, Riverside; 2017. [cited 2021 Apr 11]. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10286555.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Caulkins BG. Enzymatic Intermediates of Tryptophan Synthase at Atomic Resolution Using Solid-State NMR. [Thesis]. University of California, Riverside; 2017. Available from: http://pqdtopen.proquest.com/#viewpdf?dispub=10286555

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Wayne State University

17. Psciuk, Brian Thomas. Exploring Molecular Systems From Chemical Physics To Biochemistry Using Classical And Quantum Mechanics.

Degree: PhD, Chemistry, 2013, Wayne State University

URL: https://digitalcommons.wayne.edu/oa_dissertations/688

► Six topic are considered in this dissertation. Chapter 2 is an investigation into the role of ultra-fast hydrogen dynamics in determining fragmentation products of… (more)

▼ Six topic are considered in this dissertation. Chapter 2 is an investigation into the role of ultra-fast hydrogen dynamics in determining fragmentation products of C3H4 following exposure to intense laser fields. Classical dynamics simulations were performed starting from C3H4 isomers with 190 - 240 kcal/mol excess energy distributed randomly as nuclear momenta. Deprotonation events were seen in ca. 50 - 75 % of all trajectories. Roughly one third of all trajectories showed fragmentation involving internal isomerization prior to dissociation. Chapter 3 is a survey of currently popular density functional methods and their ability to calculate accurate excitation energies and intensities of some organic molecules and simple first row transition metal complexes. Choice of a reasonable basis set seemed to have little effect on the calculated electronic spectra of the inorganic complexes. Long-range corrected functionals and hybrid density functionals seemed to perform relatively well with only slight underestimations in either energies or intensities. Chapters 4 and 5 probe the structural and aromatic properties for a novel class of second row transition metal metallapyrimidine compounds. Aromaticity was gauged using Nucleus Independent Chemical Shift calculations and Natural Chemical Shielding analysis by obtaining ring π orbital contributions to the calculated chemical shift. The paramagnetic contribution to the chemical shift was used as an enhanced metric for determining aromaticity in metallacycle compounds. Metallapyrimidines containing metals with no valence d orbitals were found to be no better than weakly aromatic, while metals with valence d orbitals can be quite aromatic. Chapter 6 documents the force field parameterization for 50 modified DNA and 107 naturally occurring modified RNA nucleosides. Hartree-Fock calculations were used with a restraining procedure to generate atom-centered partial charges for use in molecular dynamics simulations using the AMBER force field. The parameters will allow AMBER and other similar force fields method users to incorporate modified nucleosides into their classical simulations. Chapters 7 and 8 detail the development of a computational method for computing accurate acid dissociation constants and solution phase oxidation potentials of canonical nucleic acid residues in addition to intermediates and products of guanine oxidation. Using implicit solvent modeling and accounting for relevant tautomers and protonation states present in aqueous solution, the trends in the calculated oxidation potentials were found to be in relatively good agreement with the trends in experimentally measured potentials. The methodology was then used to map out the pKa's and redox potentials of pathways for guanine oxidation. Advisors/Committee Members: H. Bernhard Schlegel.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Psciuk, B. T. (2013). Exploring Molecular Systems From Chemical Physics To Biochemistry Using Classical And Quantum Mechanics. (Doctoral Dissertation). Wayne State University. Retrieved from https://digitalcommons.wayne.edu/oa_dissertations/688

Chicago Manual of Style (16^th Edition):

Psciuk, Brian Thomas. “Exploring Molecular Systems From Chemical Physics To Biochemistry Using Classical And Quantum Mechanics.” 2013. Doctoral Dissertation, Wayne State University. Accessed April 11, 2021. https://digitalcommons.wayne.edu/oa_dissertations/688.

MLA Handbook (7^th Edition):

Psciuk, Brian Thomas. “Exploring Molecular Systems From Chemical Physics To Biochemistry Using Classical And Quantum Mechanics.” 2013. Web. 11 Apr 2021.

Vancouver:

Psciuk BT. Exploring Molecular Systems From Chemical Physics To Biochemistry Using Classical And Quantum Mechanics. [Internet] [Doctoral dissertation]. Wayne State University; 2013. [cited 2021 Apr 11]. Available from: https://digitalcommons.wayne.edu/oa_dissertations/688.

Council of Science Editors:

Psciuk BT. Exploring Molecular Systems From Chemical Physics To Biochemistry Using Classical And Quantum Mechanics. [Doctoral Dissertation]. Wayne State University; 2013. Available from: https://digitalcommons.wayne.edu/oa_dissertations/688

Washington State University

18. [No author]. Using Raman Spectroscopy to Probe the Internal Structure and Excitonic Properties of Light-Harvesting Aggregates of Tetra(sulfonatophenyl)porphyrin .

Degree: 2013, Washington State University

URL: http://hdl.handle.net/2376/4759

► Borrowing ideas from light-harvesting aggregates in nature for use in photovoltaics or solar fuels to improve light collection and solar energy efficiency is an attractive… (more)

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

author], [. (2013). Using Raman Spectroscopy to Probe the Internal Structure and Excitonic Properties of Light-Harvesting Aggregates of Tetra(sulfonatophenyl)porphyrin . (Thesis). Washington State University. Retrieved from http://hdl.handle.net/2376/4759

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

author], [No. “Using Raman Spectroscopy to Probe the Internal Structure and Excitonic Properties of Light-Harvesting Aggregates of Tetra(sulfonatophenyl)porphyrin .” 2013. Thesis, Washington State University. Accessed April 11, 2021. http://hdl.handle.net/2376/4759.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

author], [No. “Using Raman Spectroscopy to Probe the Internal Structure and Excitonic Properties of Light-Harvesting Aggregates of Tetra(sulfonatophenyl)porphyrin .” 2013. Web. 11 Apr 2021.

Vancouver:

author] [. Using Raman Spectroscopy to Probe the Internal Structure and Excitonic Properties of Light-Harvesting Aggregates of Tetra(sulfonatophenyl)porphyrin . [Internet] [Thesis]. Washington State University; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/2376/4759.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

author] [. Using Raman Spectroscopy to Probe the Internal Structure and Excitonic Properties of Light-Harvesting Aggregates of Tetra(sulfonatophenyl)porphyrin . [Thesis]. Washington State University; 2013. Available from: http://hdl.handle.net/2376/4759

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Washington State University

19. [No author]. Pressure-induced physical and chemical changes of non-conventional energetic materials: Nitrate, perchlorate and peroxide chemistries at high pressure and high temperature .

Degree: 2015, Washington State University

URL: http://hdl.handle.net/2376/5502

► Non-conventional explosives are widely used in terrorist activities, thus imposing a threat to homeland security. The simple combination of oxidizers with fuels is one popular… (more)

▼ Non-conventional explosives are widely used in terrorist activities, thus imposing a threat to homeland security. The simple combination of oxidizers with fuels is one popular category. Our goal is to explore and understand chemistry in selected oxidizers over a relevant pressure-temperature (P-T) regime of blast conditions, to get insights into fundamental chemistry associated with the selected energetic molecules and energetic processes at molecular level, for mitigation applications. We have investigated ammonium nitrate (AN), ammonium perchlorate (AP), and simple group IA peroxides under high-pressure high-temperature conditions, using confocal micro-Raman spectroscopy and synchrotron x-ray diffraction. AN studies conducted up to 50 GPa and 450 °C provide new constraints for its phase diagram. The spectral evidence confirms the presence of phase IV´ in a wide range of both thermal and chemical conditions. The strengthening of hydrogen bonding observed for phase IV´ influences the melt-decomposition line, showing an unusual turnover of decomposition temperature. We have proposed two models for decomposition, based on the phase from which it occurs. In addition, we observed an enhanced stability for phase IV in different chemical environments.AP studies conducted up to 50 GPa and 450 °C show spectral evidence for three new ordered phases (III, IV and VI) at various P-T conditions with varying degrees of hydrogen bonding. Decomposition occurs from phase V which we suggest to be initiated via a diffusion pathway. The proposed phase diagram shows a rich polymorphism and replacement of melt from a decomposition line.Both Li2O2 and Na2O2 studies show evidence for pressure-induced phase and chemical transitions, similar to H2O2. We observed comparatively higher transition pressures for both phase I → II and chemical decomposition transitions in Li2O2. This suggests the influence of the degree of intermolecular interactions on transition pressures. The orthorhombic Li2O2 phase II with enhanced stability is a structure with different packing. Unlike nitrates and perchlorates, alkali metal peroxides are the only type of oxidizers considered in this study in which hydrogen bonding is absent. Our results show that both the presence of hydrogen bonding and its degree have varying effects on their decomposition mechanisms and transition pressures and temperatures. Advisors/Committee Members: Yoo, Choong-Shik (advisor).

Subjects/Keywords: Chemistry; Physical chemistry

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APA (6^th Edition):

author], [. (2015). Pressure-induced physical and chemical changes of non-conventional energetic materials: Nitrate, perchlorate and peroxide chemistries at high pressure and high temperature . (Thesis). Washington State University. Retrieved from http://hdl.handle.net/2376/5502

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

author], [No. “Pressure-induced physical and chemical changes of non-conventional energetic materials: Nitrate, perchlorate and peroxide chemistries at high pressure and high temperature .” 2015. Thesis, Washington State University. Accessed April 11, 2021. http://hdl.handle.net/2376/5502.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

author], [No. “Pressure-induced physical and chemical changes of non-conventional energetic materials: Nitrate, perchlorate and peroxide chemistries at high pressure and high temperature .” 2015. Web. 11 Apr 2021.

Vancouver:

author] [. Pressure-induced physical and chemical changes of non-conventional energetic materials: Nitrate, perchlorate and peroxide chemistries at high pressure and high temperature . [Internet] [Thesis]. Washington State University; 2015. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/2376/5502.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

author] [. Pressure-induced physical and chemical changes of non-conventional energetic materials: Nitrate, perchlorate and peroxide chemistries at high pressure and high temperature . [Thesis]. Washington State University; 2015. Available from: http://hdl.handle.net/2376/5502

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Colorado

20. Cuadra-Rodriguez, Luis Alberto. Design and Development of a Droplet Mass Spectrometer.

Degree: PhD, Chemistry & Biochemistry, 2011, University of Colorado

URL: https://scholar.colorado.edu/chem_gradetds/29

► A droplet mass spectrometer has been built to study the oxidation of salt-water droplets coated by organic surfactants. These studies are to model the… (more)

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Cuadra-Rodriguez, L. A. (2011). Design and Development of a Droplet Mass Spectrometer. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chem_gradetds/29

Chicago Manual of Style (16^th Edition):

Cuadra-Rodriguez, Luis Alberto. “Design and Development of a Droplet Mass Spectrometer.” 2011. Doctoral Dissertation, University of Colorado. Accessed April 11, 2021. https://scholar.colorado.edu/chem_gradetds/29.

MLA Handbook (7^th Edition):

Cuadra-Rodriguez, Luis Alberto. “Design and Development of a Droplet Mass Spectrometer.” 2011. Web. 11 Apr 2021.

Vancouver:

Cuadra-Rodriguez LA. Design and Development of a Droplet Mass Spectrometer. [Internet] [Doctoral dissertation]. University of Colorado; 2011. [cited 2021 Apr 11]. Available from: https://scholar.colorado.edu/chem_gradetds/29.

Council of Science Editors:

Cuadra-Rodriguez LA. Design and Development of a Droplet Mass Spectrometer. [Doctoral Dissertation]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/chem_gradetds/29

University of Colorado

21. Abdelhaq, Mirvat. Design, Synthesis a nd Characterization of Ruthenium Polypyridyl Complexes Towards Structural and Conformational Control of Intramolecular Electron Transfer.

Degree: PhD, Chemistry & Biochemistry, 2012, University of Colorado

URL: https://scholar.colorado.edu/chem_gradetds/62

► The demand for carbon neutral sources of energy has led researchers to turn toward strategies involving conversion of solar photons to produce electricity and… (more)

▼ The demand for carbon neutral sources of energy has led researchers to turn toward strategies involving conversion of solar photons to produce electricity and fuels. Solar conversion is initiated by photoinduced electron transfer (ET) processes. Donor-Bridge-Acceptor (DBA) complexes are a common platform for investigating photoinduced intramolecular electron transfer processes. In this work, two series of DBA complexes have been synthesized and characterized to investigate the role of structural elements on rates of photoinduced intramolecular electron transfer. The DBA complexes are comprised of a ruthenium polypyridyl donor covalently linked to a 4,4'-bipyridinium acceptor by a bridging aryl subunit. We hypothesize that the addition of steric bulk on the donor chromophore and the bridging subunit will alter the lifetimes for forward and back electron transfer processes. New electroactive asymmetric ligands were synthesized in high yields and complexed to produce seven new DBA complexes which were characterized by absorption and emission spectroscopies, cyclic voltammetry and spectroelectrochemistry, electronic structure calculations and picosecond transient absorption techniques. The first series of DBA complexes was prepared to investigate how lifetimes of intramolecular ET are affected by increased methylation on ancillary ligands which is expected to alter driving forces for ET. The electron lifetimes were measured for three complexes that share an electroactive ligand but differ in ancillary ligand. It was determined that the lifetime for forward ET was not significantly altered but the lifetimes for back ET differed by a factor of two. For the second DBA series, methyl groups were systematically introduced onto various positions of the bridging subunit to determine if steric bulk is effective at disrupting electron communication within the complex thereby altering ET lifetimes. Reductive spectroelectrochemistry and transient absorption spectra revealed that steric bulk was effective at localizing electron density onto the acceptor moiety. The measured ET lifetimes showed that the number of methyl substituents on the bridging subunit was more of a determining factor of ET lifetimes than the methyl substituent position. Advisors/Committee Members: Niels H. Damrauer, Gordana Dukovic, Tarek Sammakia, Veronica Bierbaum, Jerry Peterson.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Abdelhaq, M. (2012). Design, Synthesis a nd Characterization of Ruthenium Polypyridyl Complexes Towards Structural and Conformational Control of Intramolecular Electron Transfer. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chem_gradetds/62

Chicago Manual of Style (16^th Edition):

Abdelhaq, Mirvat. “Design, Synthesis a nd Characterization of Ruthenium Polypyridyl Complexes Towards Structural and Conformational Control of Intramolecular Electron Transfer.” 2012. Doctoral Dissertation, University of Colorado. Accessed April 11, 2021. https://scholar.colorado.edu/chem_gradetds/62.

MLA Handbook (7^th Edition):

Abdelhaq, Mirvat. “Design, Synthesis a nd Characterization of Ruthenium Polypyridyl Complexes Towards Structural and Conformational Control of Intramolecular Electron Transfer.” 2012. Web. 11 Apr 2021.

Vancouver:

Abdelhaq M. Design, Synthesis a nd Characterization of Ruthenium Polypyridyl Complexes Towards Structural and Conformational Control of Intramolecular Electron Transfer. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2021 Apr 11]. Available from: https://scholar.colorado.edu/chem_gradetds/62.

Council of Science Editors:

Abdelhaq M. Design, Synthesis a nd Characterization of Ruthenium Polypyridyl Complexes Towards Structural and Conformational Control of Intramolecular Electron Transfer. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/chem_gradetds/62

University of Colorado

22. Peters, Willliam Kenneth. Carrier Dynamics in Nanocrystalline Lead Salts and Non-Adiabatic Dynamics in Near-Degenerate States of Molecules.

Degree: PhD, Chemistry & Biochemistry, 2012, University of Colorado

URL: https://scholar.colorado.edu/chem_gradetds/73

► Degenerate femtosecond pump-probe transient absorption measurements are presented of hot carrier dynamics following above band-edge absorption in colloidal lead sulfide quantum dots. A transient… (more)

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Peters, W. K. (2012). Carrier Dynamics in Nanocrystalline Lead Salts and Non-Adiabatic Dynamics in Near-Degenerate States of Molecules. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chem_gradetds/73

Chicago Manual of Style (16^th Edition):

Peters, Willliam Kenneth. “Carrier Dynamics in Nanocrystalline Lead Salts and Non-Adiabatic Dynamics in Near-Degenerate States of Molecules.” 2012. Doctoral Dissertation, University of Colorado. Accessed April 11, 2021. https://scholar.colorado.edu/chem_gradetds/73.

MLA Handbook (7^th Edition):

Peters, Willliam Kenneth. “Carrier Dynamics in Nanocrystalline Lead Salts and Non-Adiabatic Dynamics in Near-Degenerate States of Molecules.” 2012. Web. 11 Apr 2021.

Vancouver:

Peters WK. Carrier Dynamics in Nanocrystalline Lead Salts and Non-Adiabatic Dynamics in Near-Degenerate States of Molecules. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2021 Apr 11]. Available from: https://scholar.colorado.edu/chem_gradetds/73.

Council of Science Editors:

Peters WK. Carrier Dynamics in Nanocrystalline Lead Salts and Non-Adiabatic Dynamics in Near-Degenerate States of Molecules. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/chem_gradetds/73

Iowa State University

23. Boschen, Jeffery. Where to draw the line: Chasing energy extrapolations, cluster convergence, and molecular trajectories.

Degree: 2017, Iowa State University

URL: https://lib.dr.iastate.edu/etd/15493

► The adsorption of S on Cu surfaces is studied by density functional theory using both plane-wave and atomic orbital basis sets. Calculations are performed on… (more)

▼ The adsorption of S on Cu surfaces is studied by density functional theory using both plane-wave and atomic orbital basis sets. Calculations are performed on Cu clusters of increasing sizes, and strong oscillations in the S-Cu binding energy versus cluster size are found. Although expected for small clusters, the oscillations persist even to clusters containing a few hundred atoms. Smearing of the occupancy function in plane-wave DFT, and averaging over clusters of different sizes are presented as possible approaches to approximate bulk results using small to medium sized clusters. Chemically accurate potential energy curves for the lowest lying singlet states of C2 are obtained using the correlation energy extrapolation by intrinsic scaling (CEEIS) method. The potential energies also include complete basis set extrapolation, core-valence correlation, spin-orbit coupling, and scalar relativistic effects. Our calculated ro-vibrational levels show deviations from experiment of between ~10-20 cm-1, demonstrating near spectroscopic accuracy. The correlation energy extrapolation by many-body expansion (CEEMBE) method is presented. Like the CEEIS method, CEEMBE approximates configuration interaction (CI) energies using a linear extrapolation from CI calculations with reduced numbers of virtual orbitals. The method also uses a many-body expansion of the CI energy based on separating the valence orbitals into groups. Tests on ozone and F2 potential energy surfaces show that CI energies can be reproduced to within a few millihartree, and in many cases to within less than 1 millihartree. We also present a hybrid methodology, CEEMBE-h, which adds CEEIS style extrapolations to the CEEMBE procedure. CEEMBE-h reproduces the original CEEMBE energies to within 0.1-0.5 millihartree or less. Nonadiabatic dynamics using spin-flip time-dependent density functional theory (SF-TDDFT) are presented for the penta-2,4-dieniminium cation. We developed an interface between the GAMESS and Newton-X programs for SF-TDDFT dynamics. Time-derivative couplings between SF-TDDFT states are calculated using an approximate wavefunction overlap method. Our comparison with analytical couplings from CASSCF demonstrates that the overlap method for time-derivative couplings is effective for SF-TDDFT. Because of the spin-contamination in SF-TDDFT, the interface includes a state-tracking algorithm to ensure dynamics are propagated on the correct potential energy surface.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Boschen, J. (2017). Where to draw the line: Chasing energy extrapolations, cluster convergence, and molecular trajectories. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/15493

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Boschen, Jeffery. “Where to draw the line: Chasing energy extrapolations, cluster convergence, and molecular trajectories.” 2017. Thesis, Iowa State University. Accessed April 11, 2021. https://lib.dr.iastate.edu/etd/15493.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Boschen, Jeffery. “Where to draw the line: Chasing energy extrapolations, cluster convergence, and molecular trajectories.” 2017. Web. 11 Apr 2021.

Vancouver:

Boschen J. Where to draw the line: Chasing energy extrapolations, cluster convergence, and molecular trajectories. [Internet] [Thesis]. Iowa State University; 2017. [cited 2021 Apr 11]. Available from: https://lib.dr.iastate.edu/etd/15493.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Boschen J. Where to draw the line: Chasing energy extrapolations, cluster convergence, and molecular trajectories. [Thesis]. Iowa State University; 2017. Available from: https://lib.dr.iastate.edu/etd/15493

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Washington

24. Lestrange, Patrick Joseph. Modeling core excitations and preserving spin symmetry in molecular systems.

Degree: PhD, 2017, University of Washington

URL: http://hdl.handle.net/1773/39983

► This dissertation details work in two general areas: the modeling of X-ray absorption spectroscopy (XAS) and the spin symmetry in molecular simulations. The first chapter… (more)

Subjects/Keywords:

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APA (6^th Edition):

Lestrange, P. J. (2017). Modeling core excitations and preserving spin symmetry in molecular systems. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/39983

Chicago Manual of Style (16^th Edition):

Lestrange, Patrick Joseph. “Modeling core excitations and preserving spin symmetry in molecular systems.” 2017. Doctoral Dissertation, University of Washington. Accessed April 11, 2021. http://hdl.handle.net/1773/39983.

MLA Handbook (7^th Edition):

Lestrange, Patrick Joseph. “Modeling core excitations and preserving spin symmetry in molecular systems.” 2017. Web. 11 Apr 2021.

Vancouver:

Lestrange PJ. Modeling core excitations and preserving spin symmetry in molecular systems. [Internet] [Doctoral dissertation]. University of Washington; 2017. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1773/39983.

Council of Science Editors:

Lestrange PJ. Modeling core excitations and preserving spin symmetry in molecular systems. [Doctoral Dissertation]. University of Washington; 2017. Available from: http://hdl.handle.net/1773/39983

Iowa State University

25. Pruitt, Spencer. Speed and accuracy: Having your cake and eating it too.

Degree: 2012, Iowa State University

URL: https://lib.dr.iastate.edu/etd/12441

► Since the first ab initio methods were developed, the ultimate goal of quantum chemistry has been to provide insights, not readily accessible through experiment, into… (more)

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Pruitt, S. (2012). Speed and accuracy: Having your cake and eating it too. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/12441

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pruitt, Spencer. “Speed and accuracy: Having your cake and eating it too.” 2012. Thesis, Iowa State University. Accessed April 11, 2021. https://lib.dr.iastate.edu/etd/12441.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pruitt, Spencer. “Speed and accuracy: Having your cake and eating it too.” 2012. Web. 11 Apr 2021.

Vancouver:

Pruitt S. Speed and accuracy: Having your cake and eating it too. [Internet] [Thesis]. Iowa State University; 2012. [cited 2021 Apr 11]. Available from: https://lib.dr.iastate.edu/etd/12441.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pruitt S. Speed and accuracy: Having your cake and eating it too. [Thesis]. Iowa State University; 2012. Available from: https://lib.dr.iastate.edu/etd/12441

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Washington

26. Samai, Soumyadyuti. Reversibly Reconfigurable Plasmonic Nanomaterials.

Degree: PhD, 2018, University of Washington

URL: http://hdl.handle.net/1773/40858

► University of Washington Abstract Reversibly Reconfigurable Plasmonic Nanomaterials Soumyadyuti Samai Chair of the Supervisory Committee: Professor David S. Ginger Department of Chemistry Plasmonic nanoparticles have… (more)

▼ University of Washington Abstract Reversibly Reconfigurable Plasmonic Nanomaterials Soumyadyuti Samai Chair of the Supervisory Committee: Professor David S. Ginger Department of Chemistry Plasmonic nanoparticles have been extensively investigated in various fields, ranging from biosensing to nanophotonics, due to their characteristic optical features arising from localized surface plasmon resonance. A number of efforts have been made to tailor the optical properties of the nanoparticles by controlling their shape, size and chemical compositions that have advanced their applications in catalysis, molecular diagnostics, therapeutics, and designing electronic devices. Optical signatures of plasmonic nanoparticle assemblies depend on the near field coupling between the plasmon modes of the constituent particles that can be modulated by the distance and orientation between the particles. While the first-generation of plasmonic nanomaterials attempts to control the distance and directionality of the interparticle coupling by employing chemical reagents, recent developments to introduce stimulus-responsivity in the nanomaterials provide us opportunities to control the functional and optical properties of the such materials with external reagents such as light, heat, pH, electric field etc. These emerging plasmonic nanomaterials allow reversible reconfiguration of the structure that can be manipulated remotely, in a reagent-free manner, allowing reusability of the materials in all the applications. Such reconfigurable nanomaterials are obtained by combining the plasmonic nanoparticles with stimulus-sensitive materials. In this dissertation, I explore the use of photo-responsive DNA and thermo-responsive polymer poly(N-isopropylacrylamide) (PNIPAM) hydrogels, to construct reconfigurable assembly of plasmonic nanoparticles and characterize the reversible change in their optical properties in response to external stimuli. DNA has been a powerful material in nanotechnology for engineering 3D plasmonic structures, plasmon rulers and chiral nanophotonic elements. Not only the length and structural conformations of the DNA allow a precise tuning of interparticle distance and geometry of the nanostructures, but also it matches with the decay length of the near-field plasmon coupling. Recent advents of the azobenzene-phosphoramidite chemistry have facilitated the design of photo-responsive nanomaterials assembly, where the structural reconfiguration and the optical properties are controlled by the reversible trans-to-cis azobenzene photoisomerization. Such nanomaterials have found potential applications in low-cost, remote plasmonic biosensing, and optically active nanodevices. The functionality of such optically reconfigurable nanomaterials is extremely sensitive to efficiency of azobenzene photoisomerization in the DNA sequences. So, in chapter 3, we study the trans-to-cis photoisomerization of azobenzene-modified DNAs by measuring the photoisomerization quantum yields in different DNA sequences at various temperatures. Notably we… Advisors/Committee Members: Ginger, David S. (advisor).

Subjects/Keywords:

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APA (6^th Edition):

Samai, S. (2018). Reversibly Reconfigurable Plasmonic Nanomaterials. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/40858

Chicago Manual of Style (16^th Edition):

Samai, Soumyadyuti. “Reversibly Reconfigurable Plasmonic Nanomaterials.” 2018. Doctoral Dissertation, University of Washington. Accessed April 11, 2021. http://hdl.handle.net/1773/40858.

MLA Handbook (7^th Edition):

Samai, Soumyadyuti. “Reversibly Reconfigurable Plasmonic Nanomaterials.” 2018. Web. 11 Apr 2021.

Vancouver:

Samai S. Reversibly Reconfigurable Plasmonic Nanomaterials. [Internet] [Doctoral dissertation]. University of Washington; 2018. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1773/40858.

Council of Science Editors:

Samai S. Reversibly Reconfigurable Plasmonic Nanomaterials. [Doctoral Dissertation]. University of Washington; 2018. Available from: http://hdl.handle.net/1773/40858

Purdue University

27. Buchanan, Evan Gardner. Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters.

Degree: PhD, Chemistry, 2014, Purdue University

URL: https://docs.lib.purdue.edu/open_access_dissertations/236

► A central theme specific to this dissertation concerns the conformation-specific spectroscopy of flexible molecules in an effort to bridge the complexity gap. Generally, molecules… (more)

▼ A central theme specific to this dissertation concerns the conformation-specific spectroscopy of flexible molecules in an effort to bridge the complexity gap. Generally, molecules in the complexity gap have several flexible coordinates yet conformational isomerization still occurs along a simple reaction coordinate on the potential energy surface. Molecules in this regime benefit greatly from experiments probing the potential energy surfaces and provide a means to develop and test new theories in an effort to explain more complex system. These measurements are possible through the utilization of a supersonic jet expansion to collisionally cool molecules into their vibrational zero-point levels, collapsing the distribution of conformational isomers to the lowest-energy minima on the potential energy surface. This collisional cooling afforded by the expansion allows researchers to study transient species, molecular cluters, radicals and ions in a conformation-specific fashion. Overall, this dissertation contains three sets of molecules in an effort to bridge the complexity gap: synthetic foldamers, multichromophores, and water containing complexes. ^ For the synthetic foldamers, a set of 21 conformations that represent the full range of H-bonded structures were chosen to characterize the conformational dependence of the vibrational frequencies and infrared intensities of the local amide I and amide II modes and their amide I/I and amide II/II coupling constants. These amide I/I and amide II/II coupling constants remain similar in size for α-, β-, and γ-peptides despite the increasing number of C-C bonds separating the amide groups. These findings provide a simple, unifying picture for future attempts to base the calculation of both nearest-neighbor and next-nearest-neighbor coupling constants on a joint footing ^ There are numerous circumstances of fundamental importance in which two or more ultraviolet chromophores are in close proximity, influencing the intrinsic properties of the close lying, vibronically coupled excited states. Whether incorporated in the same molecule or present as separate monomers, the excited state properties depend on the distance, relative orientation, and strength of the electronic coupling between the two chromophores. Our focus here is then the conformational dependent vibronic coupling observed between ultraviolet chromophores, and the effects of adding a single water molecule or network of water molecules on the vibronic coupling. Advisors/Committee Members: Timothy Zwier, Timothy Zwier, Scott A. McLuckey, Dor Ben-Amotz, Lyudmila Slipchenko.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA (6^th Edition):

Buchanan, E. G. (2014). Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters. (Doctoral Dissertation). Purdue University. Retrieved from https://docs.lib.purdue.edu/open_access_dissertations/236

Chicago Manual of Style (16^th Edition):

Buchanan, Evan Gardner. “Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters.” 2014. Doctoral Dissertation, Purdue University. Accessed April 11, 2021. https://docs.lib.purdue.edu/open_access_dissertations/236.

MLA Handbook (7^th Edition):

Buchanan, Evan Gardner. “Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters.” 2014. Web. 11 Apr 2021.

Vancouver:

Buchanan EG. Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters. [Internet] [Doctoral dissertation]. Purdue University; 2014. [cited 2021 Apr 11]. Available from: https://docs.lib.purdue.edu/open_access_dissertations/236.

Council of Science Editors:

Buchanan EG. Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters. [Doctoral Dissertation]. Purdue University; 2014. Available from: https://docs.lib.purdue.edu/open_access_dissertations/236

28. Flister, Matthew. S-Nitrosothiols: Electronic Structure and Substituent Effects.

Degree: 2015, Marquette University

URL: https://epublications.marquette.edu/dissertations_mu/594

► S-nitrosothiols (RSNOs) are biologically important molecules involved in the storage and transport of nitric oxide (NO) and account for much of its signaling activity in… (more)

▼ S-nitrosothiols (RSNOs) are biologically important molecules involved in the storage and transport of nitric oxide (NO) and account for much of its signaling activity in living organisms. RSNOs have significant impact on NO signaling through, S-nitrosation, a major post-translational modification of proteins. These unstable thiol derivatives readily undergo homolytic dissociation of the S–N bond to release NO. RSNOs have potential therapeutic applications as NO donors, although the development of novel RSNOs has been slow due to the complex electronic structure of the –SNO group. A specific focus on the impact of the –R group on RSNO properties via substituent effect study, should serve as a reliable means for systematic development of new RSNOs. In this work, electronic structure calculations have been used to investigate substituent effects in RSNOs. A library of substituents was developed for substitution in several RSNO models, with emphasis on aromatic RSNOs (ArSNOs). Para-substituted PhSNOs showed a significant substituent effect despite the lack of conjugation between the –SNO group and substituent due to the non-planar nature of the –SNO group with the aromatic ring. A thorough computational study of PhSNO as the parent ArSNO revealed the primary mode of substituent effect, a novel cascading double conjugation. This conjugation motif involves the long-range delocalization of electron density from the oxygen lone pair to σSN* orbital and then to the phenyl ring π-system, effectively connecting the –SNO group and substituent positions of the aromatic ring. Detailed analysis of vinyl-substituted RSNO (VinSNO) was performed to further understand the fundamental interaction of a π-system with an adjacent –SNO group. The impact of the vinyl π-bond on the adjacent –SNO group of VinSNO again revealed cascading double conjugation as the dominant feature. In general, cascading double conjugation will effectively destabilize the S–N bond in ArSNOs, specifically those RSNOs with a π-system adjacent to the –SNO group. Computational study of PhSNO and VinSNO was also carried out using Lewis acids and external electric fields (EEFs) to explore their effect on the –SNO group as well as the cascading double conjugation. Application of both resulted in substantial modulation of the –SNO group properties. Furthermore, use of Lewis acids or EEF, in tandem with select substituents, is expected to improve the functionality of ArSNOs as NO donors and advance the development of novel RSNOs. Advisors/Committee Members: Timerghazin, Qadir K., Reid, Scott, Dockendorff, Chris.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Flister, M. (2015). S-Nitrosothiols: Electronic Structure and Substituent Effects. (Thesis). Marquette University. Retrieved from https://epublications.marquette.edu/dissertations_mu/594

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Flister, Matthew. “S-Nitrosothiols: Electronic Structure and Substituent Effects.” 2015. Thesis, Marquette University. Accessed April 11, 2021. https://epublications.marquette.edu/dissertations_mu/594.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Flister, Matthew. “S-Nitrosothiols: Electronic Structure and Substituent Effects.” 2015. Web. 11 Apr 2021.

Vancouver:

Flister M. S-Nitrosothiols: Electronic Structure and Substituent Effects. [Internet] [Thesis]. Marquette University; 2015. [cited 2021 Apr 11]. Available from: https://epublications.marquette.edu/dissertations_mu/594.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Flister M. S-Nitrosothiols: Electronic Structure and Substituent Effects. [Thesis]. Marquette University; 2015. Available from: https://epublications.marquette.edu/dissertations_mu/594

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

29. Bai, Yubin. Applications of Hyperpolarized Xenon-129 Nmr and Chemical Exchange Saturation Transfer in Biosensing.

Degree: 2014, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/1199

► Modern clinical applications require precise positional and temporal information regarding pathological changes in cells and tissues. For example, in magnetic resonance microscopy, better than 100… (more)

▼ Modern clinical applications require precise positional and temporal information regarding pathological changes in cells and tissues. For example, in magnetic resonance microscopy, better than 100 sq. micros per voxel spatial resolution is necessary for imaging capillary blood vessels. And in order to monitor the blood flows in brain tissues, a series of images must be acquired in less than 2 s intervals. Further, molecular imaging aims at visualizing molecules and molecular events that occur at a cellular level, i.e. sensing biological events at a fundamentally microscopic level. When compared to other imaging modalities, the main advantages of magnetic resonance imaging (MRI) are its millimeter-scale spatial resolution and wide applicability achieved with minimal perturbation to in vivo systems, whereas its major drawbacks are limited sensitivity (10 protons in a million contribute to magnetic resonance) and high cost (a million US dollars each MRI scanner). One promising solution to both problems is the combination of hyperpolarized 129Xe MRI with biosensors, which offers significant sensitivity enhancement at a much lower cost. This dissertation reports my progress in hyperpolarized 129Xe nuclear magnetic resonance (NMR) studies for use in future molecular/medical MRI applications. First, I provide an overview of molecular imaging and, specifically, magnetic resonance imaging (MRI). 129Xe NMR/MRI is particularly promising as it solves solves the common problems of signal intensity and specificity (by employing biosensors). In chapter 2, I present our hyperpolarization (nuclear spin polarization) method. A hyperpolarized 129Xe chemical exchange saturation transfer (Hyper-CEST) method was also applied to lower the biosensor detection limits significantly. These experiments were made possible through the development of a home-built 129Xe hyperpolarizer, continuous-flow hyperpolarized Xe delivery setup, Hyper-CEST pulse sequence, and accompanying NMR control programs. In chapter 3, interactions between various biosensors and their target proteins have been characterized and analyzed in finer detail than previous studies. 129Xe NMR studies for biosensors targeting human carbonic anhydrase, alpha_vbeta₃ integrin, and pH changes have been carried out. In chapter 4, hyperpolarized 129Xe chemical exchange saturation transfer (Hyper-CEST) NMR experiments have demonstrated unprecedented detection sensitivity for a synthetic xenon host molecule, tri-acetic acid cryptophane. In chapter 5, to describe interactions between xenon and bacterial spores, Hyper-CEST has been successfully applied; Xe is demonstrated to be a good probe of the spore interior structure. Six spores strains with different protective layers were clearly distinguished by Xe exchanges between spore and water, observed by Hyper-CEST. Finally, these results are summarized in chapter 6.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bai, Y. (2014). Applications of Hyperpolarized Xenon-129 Nmr and Chemical Exchange Saturation Transfer in Biosensing. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/1199

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bai, Yubin. “Applications of Hyperpolarized Xenon-129 Nmr and Chemical Exchange Saturation Transfer in Biosensing.” 2014. Thesis, University of Pennsylvania. Accessed April 11, 2021. https://repository.upenn.edu/edissertations/1199.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bai, Yubin. “Applications of Hyperpolarized Xenon-129 Nmr and Chemical Exchange Saturation Transfer in Biosensing.” 2014. Web. 11 Apr 2021.

Vancouver:

Bai Y. Applications of Hyperpolarized Xenon-129 Nmr and Chemical Exchange Saturation Transfer in Biosensing. [Internet] [Thesis]. University of Pennsylvania; 2014. [cited 2021 Apr 11]. Available from: https://repository.upenn.edu/edissertations/1199.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bai Y. Applications of Hyperpolarized Xenon-129 Nmr and Chemical Exchange Saturation Transfer in Biosensing. [Thesis]. University of Pennsylvania; 2014. Available from: https://repository.upenn.edu/edissertations/1199

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Purdue University

30. Rankin, Blake M. Quantification of molecular aggregation equilibria using spectroscopic measurements and random mixing modeling.

Degree: PhD, Chemistry, 2015, Purdue University

URL: https://docs.lib.purdue.edu/open_access_dissertations/540

► Molecular aggregation equilibria, such as the binding of ligands to a central solute molecule, are prevalent throughout biological processes and energy storage devices. However,… (more)

▼ Molecular aggregation equilibria, such as the binding of ligands to a central solute molecule, are prevalent throughout biological processes and energy storage devices. However, both the sign and magnitude of hydrophobic and ionic interactions remains a subject of theoretical debate, and has yet to be experimentally determined. Here, Raman vibrational spectroscopy is combined with multivariate curve resolution (Raman-MCR) to experimentally quantify both the number of hydrophobic contacts between alcohol molecules in water and the affinity of ions for molecular hydrophobic interfaces. Furthermore, a generalized theoretical model is developed based on random statistics in which it is assumed that the concentration of each chemical species is everywhere identical to its bulk concentration. Solute-ligand (direct) and ligand-ligand (cooperative) interactions are incorporated into the RM model and validated against an exact finite lattice (FL) model.^ Comparison of the Raman-MCR experimental results and random mixing predictions imply that there are no more hydrophobic contacts in aqueous solutions of alcohols ranging from methanol to tertiary butyl alcohol than in random mixtures of the same concentration. This suggests that the interaction between small hydrophobic groups in water is weaker than thermal energy fluctuations. Thus, the corresponding water-mediated hydrophobic interaction must be repulsive, with a magnitude sufficient to negate the attractive direct van der Waals interaction between the hydrophobic groups.^ Additional Raman-MCR experimental results imply that the interaction between aqueous sodium or fluoride ions and molecular hydrophobic groups is repulsive. In contrast, the sign and magnitude of the interaction energy between iodide ions and molecular hydrophobic groups depends on the methyl group partial charge. However, the interaction energies do not significantly compete with thermal energy fluctuations. Advisors/Committee Members: Dor Ben-Amotz, Dor Ben-Amotz, Lyudmila Slipchenko, Mahdi M. Abu-Omar, Timothy S. Zwier.

Subjects/Keywords: Chemistry; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rankin, B. M. (2015). Quantification of molecular aggregation equilibria using spectroscopic measurements and random mixing modeling. (Doctoral Dissertation). Purdue University. Retrieved from https://docs.lib.purdue.edu/open_access_dissertations/540

Chicago Manual of Style (16^th Edition):

Rankin, Blake M. “Quantification of molecular aggregation equilibria using spectroscopic measurements and random mixing modeling.” 2015. Doctoral Dissertation, Purdue University. Accessed April 11, 2021. https://docs.lib.purdue.edu/open_access_dissertations/540.

MLA Handbook (7^th Edition):

Rankin, Blake M. “Quantification of molecular aggregation equilibria using spectroscopic measurements and random mixing modeling.” 2015. Web. 11 Apr 2021.

Vancouver:

Rankin BM. Quantification of molecular aggregation equilibria using spectroscopic measurements and random mixing modeling. [Internet] [Doctoral dissertation]. Purdue University; 2015. [cited 2021 Apr 11]. Available from: https://docs.lib.purdue.edu/open_access_dissertations/540.

Council of Science Editors:

Rankin BM. Quantification of molecular aggregation equilibria using spectroscopic measurements and random mixing modeling. [Doctoral Dissertation]. Purdue University; 2015. Available from: https://docs.lib.purdue.edu/open_access_dissertations/540

Open Access Theses and Dissertations