subject:(Density functional theory)

1. wang, lei. Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds.

Degree: PhD, Physics, 2016, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:674096/

► Safe storage and disposal of spent fuel rods from nuclear power plants calls for the ability to model actinide complexes and compounds in the environment.… (more)

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

wang, l. (2016). Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:674096/

Chicago Manual of Style (16^th Edition):

wang, lei. “Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds.” 2016. Doctoral Dissertation, Brown University. Accessed February 27, 2021. https://repository.library.brown.edu/studio/item/bdr:674096/.

MLA Handbook (7^th Edition):

wang, lei. “Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds.” 2016. Web. 27 Feb 2021.

Vancouver:

wang l. Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds. [Internet] [Doctoral dissertation]. Brown University; 2016. [cited 2021 Feb 27]. Available from: https://repository.library.brown.edu/studio/item/bdr:674096/.

Council of Science Editors:

wang l. Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds. [Doctoral Dissertation]. Brown University; 2016. Available from: https://repository.library.brown.edu/studio/item/bdr:674096/

Wake Forest University

2. Arter, Calvin. FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS.

Degree: 2016, Wake Forest University

URL: http://hdl.handle.net/10339/59283

► The problems associated with anthropogenic climate change arise from the reliance on fossil fuels for energy and the greenhouse gas emissions that are produced. A… (more)

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

Arter, C. (2016). FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS. (Thesis). Wake Forest University. Retrieved from http://hdl.handle.net/10339/59283

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):

Arter, Calvin. “FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS.” 2016. Thesis, Wake Forest University. Accessed February 27, 2021. http://hdl.handle.net/10339/59283.

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

MLA Handbook (7^th Edition):

Arter, Calvin. “FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS.” 2016. Web. 27 Feb 2021.

Vancouver:

Arter C. FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS. [Internet] [Thesis]. Wake Forest University; 2016. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10339/59283.

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

Council of Science Editors:

Arter C. FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS. [Thesis]. Wake Forest University; 2016. Available from: http://hdl.handle.net/10339/59283

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

Tulane University

3. Dougherty, Kelly J. Synthesis of compounds with very large specific rotations.

Degree: 2020, Tulane University

URL: https://digitallibrary.tulane.edu/islandora/object/tulane:120370

►

[email protected]

A search in a research database for “large specific rotation” or anything similar produces few articles. Large specific rotation is not commonly used… (more)

▼

[email protected]

A search in a research database for “large specific rotation” or anything similar produces few articles. Large specific rotation is not commonly used as an indicator for extraordinary chiroptical response. Alternatively, anisotropy factors obtained from circular dichroism spectra and calculated rotational strengths are more widely used to gauge chiroptical response. To another point, a search for “large chiroptical response” gives few articles that discuss pure organic compounds, and the result list is populated by organometallic clusters, nanostructures, and thin films. A search of the Reaxys database for organic compounds with [α]Ds larger than 1000 revealed that there are about 600, and there are only two that have [α]Ds larger than 10,000.30 We wondered if we could design a compound that would break the record in specific rotation and possess extraordinary chiroptical properties. Guided by time-dependent density functional theory (TD-DFT) calculations, various chiral, polycyclic aromatic compounds (PACs) were chosen as candidates to display extraordinary chiroptical properties, such as high optical rotation, strong circular dichroism, or a high degree of circularly polarized luminescence (CPL). PACs comprise a large class of organic compounds. In addition to synthetic PACs, numerous naturally occurring PACs exist in coal tar and as decomposition products of organic material. Since their pi electrons are delocalized, PACs have interesting and possibly useful electronic properties and a variety of applications. The PACs described in this dissertation, e.g., helical mesobenzanthrones, a cyclophane, are twisted pentacenes are chiral and have interesting optoelectronic properties. TD-DFT was primarily used to predict which compounds had the greatest potential to yield record-breaking specific rotations or other chiroptical properties, and ordinary DFT calculation were used to determine if these compounds had sufficiently high racemization barriers to be resolved at room temperature. With regard to specific rotation, the accuracy of TD-DFT calculations was examined by comparing experimental specific rotations to the calculated values.

1

Kelly Jane Dougherty

Advisors/Committee Members: Pascal, Jr., Robert A. (Thesis advisor), School of Science & Engineering Chemistry (Degree granting institution).

Subjects/Keywords: time-dependent density functional theory

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APA (6^th Edition):

Dougherty, K. J. (2020). Synthesis of compounds with very large specific rotations. (Thesis). Tulane University. Retrieved from https://digitallibrary.tulane.edu/islandora/object/tulane:120370

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):

Dougherty, Kelly J. “Synthesis of compounds with very large specific rotations.” 2020. Thesis, Tulane University. Accessed February 27, 2021. https://digitallibrary.tulane.edu/islandora/object/tulane:120370.

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

MLA Handbook (7^th Edition):

Dougherty, Kelly J. “Synthesis of compounds with very large specific rotations.” 2020. Web. 27 Feb 2021.

Vancouver:

Dougherty KJ. Synthesis of compounds with very large specific rotations. [Internet] [Thesis]. Tulane University; 2020. [cited 2021 Feb 27]. Available from: https://digitallibrary.tulane.edu/islandora/object/tulane:120370.

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

Council of Science Editors:

Dougherty KJ. Synthesis of compounds with very large specific rotations. [Thesis]. Tulane University; 2020. Available from: https://digitallibrary.tulane.edu/islandora/object/tulane:120370

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

University of New South Wales

4. Pham, Anh. Theoretical investigation of novel spin-polarized materials for spintronic applications.

Degree: Materials Science & Engineering, 2014, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true

► Development of spin-polarized materials is important for the realization of spintronic devices. Two approaches are taken: (i) investigating magnetism in diluted magnetic semiconductors (DMSs), and… (more)

▼ Development of spin-polarized materials is important for the realization of spintronic devices. Two approaches are taken: (i) investigating magnetism in diluted magnetic semiconductors (DMSs), and (ii) developing novel 2D materials with intrinsic spin currents. The focus of this thesis is to study these two classes of materials using the density functional (DFT) theory.The first part focuses on ZnO based DMS. The systematic study of C/N doped ZnO with defects shows that ZnO:C exhibits ferromagnetism, but dopant complex C2 tends to inhibit this property. Most importantly, the computational method plays a key role in studying DMS. Due to the popularity of hydrogenated ZnO:Co, this system is tested using the different methods. The DFT+U method shows a very specific configuration of hydrogenated Co complex can generate ferromagnetism. The inadequacies of traditional method are further exposed when the dopant geometry is compared between the hybrid functional method and normal DFT. The hybrid method includes the Fock exchange which significantly improves the description of long-range inter-atomic forces in the geometry relaxation yielding a more accurate description. The second part focuses on the study of novel 2D materials with. The studies are devoted to increase the band gap of of novel 2D materials. In silicene and germanene, it is shown that the adsorption and substitution of Tl can increase the bandgaps to 0.29 eV at a small doping limit of ~2%. In addition, Tl can also tune the conductivity of silicene from n to p types depending on the doping sites, and preserving the high mobility of the undoped structure. Furthermore, the author also predicts several new wide bandgap quantum spin Hall insulator (QSHI). QSHI is a novel material with an insulating bulk state and spin-polarized metallic edges. By modifying the surfaces through hydrogenation, the orbital interactions of Bi, Pb, Cr, Mo, and W in the low energy level are confined on two dimensional resulting in novel QSHI with giant gap and strongly correlated property. These results represent important contribution to the study of spintronic materials. First, the understanding between the theoretical method and magnetic properties in semiconductors can help to accurately predict new spintronic materials. Most importantly, the study in orbital engineering of 2D materials with hydrogenation provides new insights into the nature topological materials which have practical applications for the next generation of electronic devices. Advisors/Committee Members: Li, Sean, Materials Science & Engineering, Faculty of Science, UNSW.

Subjects/Keywords: Magnetism; Density functional theory; Spintronics

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APA (6^th Edition):

Pham, A. (2014). Theoretical investigation of novel spin-polarized materials for spintronic applications. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Pham, Anh. “Theoretical investigation of novel spin-polarized materials for spintronic applications.” 2014. Doctoral Dissertation, University of New South Wales. Accessed February 27, 2021. http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Pham, Anh. “Theoretical investigation of novel spin-polarized materials for spintronic applications.” 2014. Web. 27 Feb 2021.

Vancouver:

Pham A. Theoretical investigation of novel spin-polarized materials for spintronic applications. [Internet] [Doctoral dissertation]. University of New South Wales; 2014. [cited 2021 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true.

Council of Science Editors:

Pham A. Theoretical investigation of novel spin-polarized materials for spintronic applications. [Doctoral Dissertation]. University of New South Wales; 2014. Available from: http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true

Oregon State University

5. Schulte, Jeff B. Hard spheres within classical density functional theory and Min proteins in Escherichia coli.

Degree: PhD, Physics, 2015, Oregon State University

URL: http://hdl.handle.net/1957/55645

► This thesis reports on computational research in two different areas. I first discuss the Min-protein system found within Escherichia coli. Following this I discuss an… (more)

▼ This thesis reports on computational research in two different areas. I first discuss the Min-protein system found within Escherichia coli. Following this I discuss an extended investigation into improving free energy functionals that are used within Classical Density Functional Theory in order to model water. Chapter 2 examines the dynamics of the Min-protein system within E. Coli, which aid in regulating the process of cell division by identifying the center of the cell. While this system usually exhibits robust bipolar oscillations in a variety of cell shapes, recent experiments have shown that when the cells are mechanically deformed into wide, flattened out, irregular shapes, the spatial regularity of these oscillations breaks down. We employ widely used stochastic and deterministic models of the Min system to simulate cells with flattened shapes. The deterministic model predicts regular bipolar oscillations, in contradiction with the experimentally observed behavior, while the single molecule nature of the stochastic model, which is based on the same reaction-diffusion equations, leads to the disruption of the regular patterns of protein concentration. We further report on simulations of symmetric but flattened cell shapes, and find that it is the flattening and accompanying lateral expansion rather than the asymmetry of the cell shapes that causes the irregular oscillation behavior. Chapter 3 begins our discussion of Classical Density Functional Theory research by introducing many of the key concepts used in the following chapters. Chapter 4 investigates the value of the distribution function of an inhomogeneous hard-sphere fluid at contact. This quantity plays a critical role in statistical associating fluid theory, which is the basis of a number of recently developed classical density functionals, including ones developed within my research group. We define two averaged values for the distribution function at contact and derive formulas for each of them from the White Bear version of the fundamental measure theory functional, using an assumption of thermodynamic consistency. We test these formulas, as well as two existing formulas, against Monte Carlo simulations and find excellent agreement between the Monte Carlo data and one of our averaged distribution functions. Chapter 5 details our modifications of our recently published statistical associating fluid theory-based classical density functional theory for water, incorporating this improved distribution function at contact. We examine the effect of this alteration by studying two hard-sphere solutes and a Lennard-Jones approximation of a krypton-atom solute, and find improvement. Finally, Chapter 6 introduces an approximation for the pair distribution function of the inhomogeneous hard sphere fluid. Our approximation makes use of the new distribution function at contact referred to above. This approach achieves greater computational efficiency than previous approaches by enabling the use of exclusively fixed-kernel convolutions, which allows for an… Advisors/Committee Members: Roundy, David J. (advisor), Jansen, Henri J. (committee member).

Subjects/Keywords: Classical Density Functional Theory; Density functionals

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APA (6^th Edition):

Schulte, J. B. (2015). Hard spheres within classical density functional theory and Min proteins in Escherichia coli. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/55645

Chicago Manual of Style (16^th Edition):

Schulte, Jeff B. “Hard spheres within classical density functional theory and Min proteins in Escherichia coli.” 2015. Doctoral Dissertation, Oregon State University. Accessed February 27, 2021. http://hdl.handle.net/1957/55645.

MLA Handbook (7^th Edition):

Schulte, Jeff B. “Hard spheres within classical density functional theory and Min proteins in Escherichia coli.” 2015. Web. 27 Feb 2021.

Vancouver:

Schulte JB. Hard spheres within classical density functional theory and Min proteins in Escherichia coli. [Internet] [Doctoral dissertation]. Oregon State University; 2015. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1957/55645.

Council of Science Editors:

Schulte JB. Hard spheres within classical density functional theory and Min proteins in Escherichia coli. [Doctoral Dissertation]. Oregon State University; 2015. Available from: http://hdl.handle.net/1957/55645

NSYSU

6. Chang, Ching-Sheng. A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle.

Degree: Master, Mechanical and Electro-Mechanical Engineering, 2008, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353

► In order to understand the structural and electronic properties of titanium oxide nanoparticles of different sizes, the FIRE algorithm combining the simulated annealing method is… (more)

Subjects/Keywords: Molecular Dynamics; Density functional theory; FIRE algorithm

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APA (6^th Edition):

Chang, C. (2008). A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353

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):

Chang, Ching-Sheng. “A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle.” 2008. Thesis, NSYSU. Accessed February 27, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353.

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

MLA Handbook (7^th Edition):

Chang, Ching-Sheng. “A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle.” 2008. Web. 27 Feb 2021.

Vancouver:

Chang C. A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle. [Internet] [Thesis]. NSYSU; 2008. [cited 2021 Feb 27]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353.

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

Council of Science Editors:

Chang C. A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle. [Thesis]. NSYSU; 2008. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353

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

NSYSU

7. Lin, Wen-huan. Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study.

Degree: Master, Physics, 2011, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556

► The atomic and electronic structures of Au-intercalated graphene buffer layer on SiC(0001) surface were investigated using first-principles calculations. The unique Dirac cone of the graphene… (more)

Subjects/Keywords: graphene; SiC; Dirac point; density functional theory

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APA (6^th Edition):

Lin, W. (2011). Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556

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):

Lin, Wen-huan. “Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study.” 2011. Thesis, NSYSU. Accessed February 27, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556.

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

MLA Handbook (7^th Edition):

Lin, Wen-huan. “Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study.” 2011. Web. 27 Feb 2021.

Vancouver:

Lin W. Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study. [Internet] [Thesis]. NSYSU; 2011. [cited 2021 Feb 27]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556.

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

Council of Science Editors:

Lin W. Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study. [Thesis]. NSYSU; 2011. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556

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

8. Lehtinen, Petri Olavi. Magnetic Nature of Intrinsic Carbon Defects.

Degree: 2005, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2005/isbn951227521X/

►

Magnetism is a phenomenon that has been known for a very long time. Iron, cobalt, and nickel are known ferromagnetic materials. It is less known,… (more)

▼

Magnetism is a phenomenon that has been known for a very long time. Iron, cobalt, and nickel are known ferromagnetic materials. It is less known, probably because it is so unexpected, that even carbon can have ferromagnetic behaviour. Experimentally this has been confirmed on many occasions within the last decade. Ferromagnetic behaviour of carbon provides an example of the fact that magnetism is not well understood at the atomic scale. One of the aims of this thesis is to study and understand possible sources of ferromagnetism in carbon systems, thereby creating a possible foundation for the next generation of ferromagnets. Carbon itself is a very interesting substance with numerous interesting properties. In the late 1980s and early 1990s new carbon allotropes were found, such as fullerenes (bucky balls) and nanotubes (cylinders), next to the old ones (graphite and diamond). Especially nanotubes have been considered as candidates for several future applications. Whatever the fabrication process, all allotropes of carbon will have intrinsic defects, and in this thesis the role of these defects in carbon magnetism is investigated in detail. Studying magnetism requires "state-of-the-art"-methods due to the demand of high accuracy because energy differences between non-magnetic and magnetic cases are usually very small. Ab initio methods are usually the best for such studies, especially methods based on the density functional theory. Here, a state-of-art method which is based on the density functional theory and implementing projector augmented waves to model the properties of carbon is used. Adatoms and vacancies are found to have magnetic moments of 0.5 μB and 1.0 μB, respectively. In practice, however, the high mobility of adatoms on graphene at room temperature would suggest that many of them recombine with vacancies or cluster together, destroying their magnetism. Despite the indications that a barrier to vacancy-interstitial pair recombination exists, efficient recombination seems to be confirmed by He-irradiation experiments. The magnetic signal was small despite the fact that the amount of defects created by the He ions is large. Also, the effect of the changing electronic structure on the magnetic moments of adatoms and vacancies is studied with the help of nanotubes. On nanotubes, the magnetism of an adatom decreases because of the curvature and differences in electronic structures while the magnetic moment of a vacancy in all but strongly metallic tubes is destroyed. The experimental demonstration of induced ferromagnetism by proton irradiation on graphite indicates a promising direction for creating a magnetic carbon system in a controllable way. Simulations indicate that this is due to a combination of a hydrogen atom trapping at vacancies and pinning of mobile adatoms, producing magnetic C-H complexes and uncompensated vacancies.

Dissertations / Laboratory of Physics, Helsinki University of Technology, ISSN 1455-1802; 129

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, Laboratory of Physics.

Subjects/Keywords: density functional theory; carbon; graphite; nanotube; magnetism

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APA (6^th Edition):

Lehtinen, P. O. (2005). Magnetic Nature of Intrinsic Carbon Defects. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2005/isbn951227521X/

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):

Lehtinen, Petri Olavi. “Magnetic Nature of Intrinsic Carbon Defects.” 2005. Thesis, Helsinki University of Technology. Accessed February 27, 2021. http://lib.tkk.fi/Diss/2005/isbn951227521X/.

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

MLA Handbook (7^th Edition):

Lehtinen, Petri Olavi. “Magnetic Nature of Intrinsic Carbon Defects.” 2005. Web. 27 Feb 2021.

Vancouver:

Lehtinen PO. Magnetic Nature of Intrinsic Carbon Defects. [Internet] [Thesis]. Helsinki University of Technology; 2005. [cited 2021 Feb 27]. Available from: http://lib.tkk.fi/Diss/2005/isbn951227521X/.

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

Council of Science Editors:

Lehtinen PO. Magnetic Nature of Intrinsic Carbon Defects. [Thesis]. Helsinki University of Technology; 2005. Available from: http://lib.tkk.fi/Diss/2005/isbn951227521X/

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

9. Witte, Jonathon Kendall. Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions.

Degree: Chemistry, 2017, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/7mc3k8tm

► This thesis is primarily concerned with the development and assessment of electronic structure approaches for intermolecular interactions. Various aspects of existing approaches – most notably… (more)

Subjects/Keywords: Chemistry; Physics; density functional theory; electronic structure

10 more images…

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APA (6^th Edition):

Witte, J. K. (2017). Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/7mc3k8tm

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):

Witte, Jonathon Kendall. “Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions.” 2017. Thesis, University of California – Berkeley. Accessed February 27, 2021. http://www.escholarship.org/uc/item/7mc3k8tm.

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

MLA Handbook (7^th Edition):

Witte, Jonathon Kendall. “Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions.” 2017. Web. 27 Feb 2021.

Vancouver:

Witte JK. Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions. [Internet] [Thesis]. University of California – Berkeley; 2017. [cited 2021 Feb 27]. Available from: http://www.escholarship.org/uc/item/7mc3k8tm.

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

Council of Science Editors:

Witte JK. Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions. [Thesis]. University of California – Berkeley; 2017. Available from: http://www.escholarship.org/uc/item/7mc3k8tm

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

Cornell University

10. Zhuang, Houlong. Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications.

Degree: PhD, Materials Science and Engineering, 2014, Cornell University

URL: http://hdl.handle.net/1813/36085

► The last decade has seen an explosion of interest in two-dimensional materials, which now can be synthesized in either single or a few atomic layer… (more)

Subjects/Keywords: Single-layer materials; Density-functional theory; Semiconductors

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APA (6^th Edition):

Zhuang, H. (2014). Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/36085

Chicago Manual of Style (16^th Edition):

Zhuang, Houlong. “Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications.” 2014. Doctoral Dissertation, Cornell University. Accessed February 27, 2021. http://hdl.handle.net/1813/36085.

MLA Handbook (7^th Edition):

Zhuang, Houlong. “Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications.” 2014. Web. 27 Feb 2021.

Vancouver:

Zhuang H. Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications. [Internet] [Doctoral dissertation]. Cornell University; 2014. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1813/36085.

Council of Science Editors:

Zhuang H. Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications. [Doctoral Dissertation]. Cornell University; 2014. Available from: http://hdl.handle.net/1813/36085

Vanderbilt University

11. Cook, Brandon Girard. Quantum transport in nanodevices.

Degree: PhD, Physics, 2012, Vanderbilt University

URL: http://hdl.handle.net/1803/13739

► First-principles simulations of quantum transport in nano-devices are presented in this dissertation. First, the extension of the complex absorbing potential quantum transport framework to the… (more)

Subjects/Keywords: density functional theory; quantum electron transport

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APA (6^th Edition):

Cook, B. G. (2012). Quantum transport in nanodevices. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/13739

Chicago Manual of Style (16^th Edition):

Cook, Brandon Girard. “Quantum transport in nanodevices.” 2012. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2021. http://hdl.handle.net/1803/13739.

MLA Handbook (7^th Edition):

Cook, Brandon Girard. “Quantum transport in nanodevices.” 2012. Web. 27 Feb 2021.

Vancouver:

Cook BG. Quantum transport in nanodevices. [Internet] [Doctoral dissertation]. Vanderbilt University; 2012. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1803/13739.

Council of Science Editors:

Cook BG. Quantum transport in nanodevices. [Doctoral Dissertation]. Vanderbilt University; 2012. Available from: http://hdl.handle.net/1803/13739

Vanderbilt University

12. Driscoll, Joseph Andrew. Electron field emission in nanostructures: A first-principles study.

Degree: PhD, Physics, 2011, Vanderbilt University

URL: http://hdl.handle.net/1803/10782

► This dissertation presents the study of electron field emission from nanostructures using a first-principles computational framework. Field emission is studied under various conditions such as… (more)

▼ This dissertation presents the study of electron field emission from nanostructures using a first-principles computational framework. Field emission is studied under various conditions such as laser illumination, spin polarization, and the presence of adsorbates. Several nanostructures are considered (carbon nanowires, graphene nanoribbons, and nanotubes of varying composition) which allow general conclusions to be made. The calculations are performed using a real-space, real-time implementation of time-dependent density functional theory. In addition to field emission results, we also present rigorous evaluations of basis sets and complex absorbing potentials, both of which are needed in order to allow these demanding calculations to be performed efficiently. The best basis choice (e.g., atomic orbitals or real-space grids) depends on the structure of the system being analyzed and the physical processes involved (e.g., laser illumination). For this reason, it was important to conduct thorough tests of basis set performance, in terms of accuracy and computational efficiency. In non-periodic systems, emitted electron density can experience non-physical reflections from boundaries of the calculation volume, leading to inaccuracies. To prevent this, we used complex absorbing potentials (CAPs) to absorb density before it could reach the boundaries. We evaluate CAPs using test cases relevant to field emission calculations. Our results show that the adsorbate atoms studied significantly increase the field emission current of carbon nanotubes. We also show that short laser pulses can cause nanostructures to emit electrons with very high spatial and time resolutions. The results predict that GaN, SiC, and Si nanotubes are particularly good field emitters. The highest-current nanotube, Si, is predicted to produce currents an order of magnitude higher than BN or C nanotubes. Carbon nanotubes with various adsorbates are shown to be able to emit spin-polarized current. These are the first first-principles calculations showing spin-polarized field emission for carbon nanotubes with iron adsorbates. Finally, our results suggest that graphene nanoribbons could be extremely good field emitters. The results and computational methods discussed provide a foundation for future theoretical work in nanoscale field emission. Advisors/Committee Members: Sait Umar (committee member), Ronald Schrimpf (committee member), Sokrates Pantelides (committee member), Charles Brau (committee member), Kalman Varga (Committee Chair).

Subjects/Keywords: density functional theory; nanotubes; nanostructures; field emission

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APA (6^th Edition):

Driscoll, J. A. (2011). Electron field emission in nanostructures: A first-principles study. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10782

Chicago Manual of Style (16^th Edition):

Driscoll, Joseph Andrew. “Electron field emission in nanostructures: A first-principles study.” 2011. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2021. http://hdl.handle.net/1803/10782.

MLA Handbook (7^th Edition):

Driscoll, Joseph Andrew. “Electron field emission in nanostructures: A first-principles study.” 2011. Web. 27 Feb 2021.

Vancouver:

Driscoll JA. Electron field emission in nanostructures: A first-principles study. [Internet] [Doctoral dissertation]. Vanderbilt University; 2011. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1803/10782.

Council of Science Editors:

Driscoll JA. Electron field emission in nanostructures: A first-principles study. [Doctoral Dissertation]. Vanderbilt University; 2011. Available from: http://hdl.handle.net/1803/10782

Vanderbilt University

13. Pennycook, Timothy John. Density functional theory and scanning transmission electron microscopy: synergistic tools for materials investigation.

Degree: PhD, Physics, 2012, Vanderbilt University

URL: http://hdl.handle.net/1803/10460

► A combination of first principles density functional calculations and aberration corrected scanning transmission electron microscopy is used to investigate a number of topical issues in… (more)

Subjects/Keywords: scanning transmission electron microscopy; density functional theory

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APA (6^th Edition):

Pennycook, T. J. (2012). Density functional theory and scanning transmission electron microscopy: synergistic tools for materials investigation. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10460

Chicago Manual of Style (16^th Edition):

Pennycook, Timothy John. “Density functional theory and scanning transmission electron microscopy: synergistic tools for materials investigation.” 2012. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2021. http://hdl.handle.net/1803/10460.

MLA Handbook (7^th Edition):

Pennycook, Timothy John. “Density functional theory and scanning transmission electron microscopy: synergistic tools for materials investigation.” 2012. Web. 27 Feb 2021.

Vancouver:

Pennycook TJ. Density functional theory and scanning transmission electron microscopy: synergistic tools for materials investigation. [Internet] [Doctoral dissertation]. Vanderbilt University; 2012. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1803/10460.

Council of Science Editors:

Pennycook TJ. Density functional theory and scanning transmission electron microscopy: synergistic tools for materials investigation. [Doctoral Dissertation]. Vanderbilt University; 2012. Available from: http://hdl.handle.net/1803/10460

Vanderbilt University

14. Brock, Casey Neil. Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials.

Degree: PhD, Interdisciplinary Materials Science, 2019, Vanderbilt University

URL: http://hdl.handle.net/1803/12328

► In principle, the properties of materials are determined by the behavior of electrons. Therefore quantum mechanical electronic structure calculations play a critical role in materials… (more)

Subjects/Keywords: pseudopotentials; density functional theory; electronic structure

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APA (6^th Edition):

Brock, C. N. (2019). Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12328

Chicago Manual of Style (16^th Edition):

Brock, Casey Neil. “Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2021. http://hdl.handle.net/1803/12328.

MLA Handbook (7^th Edition):

Brock, Casey Neil. “Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials.” 2019. Web. 27 Feb 2021.

Vancouver:

Brock CN. Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1803/12328.

Council of Science Editors:

Brock CN. Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://hdl.handle.net/1803/12328

Penn State University

15. Wang, Yuanxi. Theory of two-dimensional materials: synthesis, properties, and structural engineering.

Degree: 2016, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/3b591857h

► In this dissertation, I study the synthesis (and post-synthesis modifications), properties, and structural engineering of two-dimensional materials, using atomistic modeling techniques such as empirical forcefields… (more)

▼ In this dissertation, I study the synthesis (and post-synthesis modifications), properties, and structural engineering of two-dimensional materials, using atomistic modeling techniques such as empirical forcefields and density functional theory. The dissertation is divided into four parts. The first part consists of four chapters: in Chapters 1-3 I give an overview on density functional theory and how vibrational properties and optical properties can be calculated within the DFT framework; in Chapter 4 a brief review on two-dimensional materials is given. The second part is devoted to the synthesis and post-synthesis modifications of two-dimensional materials. In Chapter 5 I investigate the intercalation of hexagonal boron nitride and graphite using Bronsted acids such as H3PO4. DFT calculations show that dipolar interactions between acids molecules and the 2D sheets drive the intercalation process. In Chapter 6 I study stripe patterns of W and Mo atoms in triangular monolayers of WxMo1-xS2 alloys. DFT calculations suggest that stripe ordering is kinetically driven, governed by fluctuations in local thermodynamic conditions during growth. In addition, I show that the striped phase alloy is electronically isotropic but vibrationally anisotropic, due to the nearly-identical electronic properties but very different atomic masses of Mo and W. The third part is devoted to computation of vibrational and optical properties of molybdenum and tungsten disulfides. In Chapter 7 we investigate the optical signatures of defect-bound excitons in monolayer WS2. I show that the optical transitions between the highest valence band and mid-gap states introduced by sulfur vacancy defects have finite transition matrix elements. These results agrees with the measured photoluminescence spectra of monolayer WS2 grown by chemical vapor deposition, where spatially resolved photoluminescence at low temperatures revealed two bound excitons. To explain the anomaly in the thermal activation energy of the bound exciton, we propose that excitons are bound to negatively charged defects where two channels of radiative recombinations are allowed. Chapter 8 focuses on intervalley scattering processes in monolayer MoS2, as probed by resonance raman spectroscopy, where the incident laser energy is varied across the A and B excitonic levels. We focus on two Raman peaks that are dispersive, a clear signature of second-order processes involving intervalley scattering. Using group theory and DFT calculations, selection rules are established for intervalley scattering processes mediated by acoustic phonons. In Chapter 9 I investigate Second Harmonic Generation (SHG) in monolayer WS2. Its second order nonlinear susceptibility is nearly three orders of magnitude larger than other common nonlinear crystals. Density functional theory calculations suggest that the origin of the large nonlinear susceptibility lies in resonance enhancement and sharp features in the joint density of states. In the final part, I explore possible methods of manipulating the… Advisors/Committee Members: Vincent Henry Crespi, Dissertation Advisor/Co-Advisor, Vincent Henry Crespi, Committee Chair/Co-Chair, Jorge Osvaldo Sofo, Committee Member, Mauricio Terrones Maldonado, Committee Member, Thomas E Mallouk, Outside Member.

Subjects/Keywords: two-dimensional materials; density functional theory

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APA (6^th Edition):

Wang, Y. (2016). Theory of two-dimensional materials: synthesis, properties, and structural engineering. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/3b591857h

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):

Wang, Yuanxi. “Theory of two-dimensional materials: synthesis, properties, and structural engineering.” 2016. Thesis, Penn State University. Accessed February 27, 2021. https://submit-etda.libraries.psu.edu/catalog/3b591857h.

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

MLA Handbook (7^th Edition):

Wang, Yuanxi. “Theory of two-dimensional materials: synthesis, properties, and structural engineering.” 2016. Web. 27 Feb 2021.

Vancouver:

Wang Y. Theory of two-dimensional materials: synthesis, properties, and structural engineering. [Internet] [Thesis]. Penn State University; 2016. [cited 2021 Feb 27]. Available from: https://submit-etda.libraries.psu.edu/catalog/3b591857h.

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

Council of Science Editors:

Wang Y. Theory of two-dimensional materials: synthesis, properties, and structural engineering. [Thesis]. Penn State University; 2016. Available from: https://submit-etda.libraries.psu.edu/catalog/3b591857h

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

Kwame Nkrumah University of Science and Technology

16. Opoku, Ernest; Arhin, Grace; Pipim, George Baffour; Adams, Anita Houston; Tia, Richard. Site‑, enantio‑ and stereo‑selectivities of the 1,3‑dipolar cycloaddition reactions of oxanorbornadiene with C,N‑disubstituted nitrones and dimethyl nitrilimines: a DFT mechanistic study.

Degree: 2020, Kwame Nkrumah University of Science and Technology

URL: Theoretical Chemistry Accounts (2020) 139:16 https://doi.org/10.1007/s00214-019-2529-8 ; http://dspace.knust.edu.gh:8080/jspui/handle/123456789/12659

►

1,3-Dipolar cycloaddition of nitrones to oxanorbornadienes is an important method for the enantioselective synthesis of highly substituted 5-membered heterocycles such as furans and isoxazolidines, which… (more)

Subjects/Keywords: Dipole; Oxanorbornadiene; Nitrone; Enantioselectivity; Density functional theory

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APA (6^th Edition):

Opoku, Ernest; Arhin, Grace; Pipim, George Baffour; Adams, Anita Houston; Tia, R. (2020). Site‑, enantio‑ and stereo‑selectivities of the 1,3‑dipolar cycloaddition reactions of oxanorbornadiene with C,N‑disubstituted nitrones and dimethyl nitrilimines: a DFT mechanistic study. (Thesis). Kwame Nkrumah University of Science and Technology. Retrieved from Theoretical Chemistry Accounts (2020) 139:16 https://doi.org/10.1007/s00214-019-2529-8 ; http://dspace.knust.edu.gh:8080/jspui/handle/123456789/12659

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):

Opoku, Ernest; Arhin, Grace; Pipim, George Baffour; Adams, Anita Houston; Tia, Richard. “Site‑, enantio‑ and stereo‑selectivities of the 1,3‑dipolar cycloaddition reactions of oxanorbornadiene with C,N‑disubstituted nitrones and dimethyl nitrilimines: a DFT mechanistic study.” 2020. Thesis, Kwame Nkrumah University of Science and Technology. Accessed February 27, 2021. Theoretical Chemistry Accounts (2020) 139:16 https://doi.org/10.1007/s00214-019-2529-8 ; http://dspace.knust.edu.gh:8080/jspui/handle/123456789/12659.

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

MLA Handbook (7^th Edition):

Opoku, Ernest; Arhin, Grace; Pipim, George Baffour; Adams, Anita Houston; Tia, Richard. “Site‑, enantio‑ and stereo‑selectivities of the 1,3‑dipolar cycloaddition reactions of oxanorbornadiene with C,N‑disubstituted nitrones and dimethyl nitrilimines: a DFT mechanistic study.” 2020. Web. 27 Feb 2021.

Vancouver:

Opoku, Ernest; Arhin, Grace; Pipim, George Baffour; Adams, Anita Houston; Tia R. Site‑, enantio‑ and stereo‑selectivities of the 1,3‑dipolar cycloaddition reactions of oxanorbornadiene with C,N‑disubstituted nitrones and dimethyl nitrilimines: a DFT mechanistic study. [Internet] [Thesis]. Kwame Nkrumah University of Science and Technology; 2020. [cited 2021 Feb 27]. Available from: Theoretical Chemistry Accounts (2020) 139:16 https://doi.org/10.1007/s00214-019-2529-8 ; http://dspace.knust.edu.gh:8080/jspui/handle/123456789/12659.

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

Council of Science Editors:

Opoku, Ernest; Arhin, Grace; Pipim, George Baffour; Adams, Anita Houston; Tia R. Site‑, enantio‑ and stereo‑selectivities of the 1,3‑dipolar cycloaddition reactions of oxanorbornadiene with C,N‑disubstituted nitrones and dimethyl nitrilimines: a DFT mechanistic study. [Thesis]. Kwame Nkrumah University of Science and Technology; 2020. Available from: Theoretical Chemistry Accounts (2020) 139:16 https://doi.org/10.1007/s00214-019-2529-8 ; http://dspace.knust.edu.gh:8080/jspui/handle/123456789/12659

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

Université de Neuchâtel

17. Battaglia, Corsin. Structural and electronic properties of self-assembled nanostructures on silicon surfaces.

Degree: 2008, Université de Neuchâtel

URL: http://doc.rero.ch/record/9568

► Cette thèse présente de nouveaux résultats sur les nanostructures auto-assemblées sur surfaces de silicium étudiées par différentes techniques complémentaires: la microscopie et spectroscopie tunnel (STM/STS)… (more)

▼ Cette thèse présente de nouveaux résultats sur les nanostructures auto-assemblées sur surfaces de silicium étudiées par différentes techniques complémentaires: la microscopie et spectroscopie tunnel (STM/STS) à basse température, la diffraction dynamique d'électron de basse énergie (LEED), la spectroscopie de photoélectrons résolue en angle (ARPES) ainsi que des calculs "ab initio" réalisés dans le cadre de la théorie de la fonctionnelle de densité (DFT). A mesure que la taille des dispositifs électroniques, magnétiques et optiques s'approche du régime nanométrique, la compréhension des phénomènes quantiques présents sur les surfaces semiconductrices est de plus en plus importante pour la science et pour la technologie. Nous investiguons ici les propriétés structurales et électroniques à l'échelle atomique de la reconstruction Si(331)-(12£1), ainsi que des chaînes atomiques auto-assemblées sur la surface de Si(111). La surface de Si(331) est importante puisque c'est la seule surface plane de silicium qui présente une reconstruction stable avec une orientation comprise entre les directions (111) et (110). Après avoir optimisé la méthode de préparation de la surface, nous sommes désormais capables d'obtenir des régions de taille quasi micrométrique où l'arrangement atomique ne présente presque aucun défaut. Cette perfection sans précédent de la surface, combinée avec son anisotropie structurale prononcée, font de cette surface un candidat prometteur pour guider la croissance auto-assemblée de réseaux de nanostructures hétéro-épitaxiales. Depuis sa découverte datant de plus de 17 ans, plusieurs modèles structuraux ont été proposés. Cependant, aucun de ces modèles n'a été capable d'expliquer nos images STM à haute résolution. En exploitant la complémentarité de STM, LEED et DFT, nous proposons un nouveau modèle structural pour la reconstruction i(331)-(12£1) et discutons sa stabilité et ses propriétés électroniques. Nous nous focalisons ensuite sur les mécanismes sous-jacents de l'auto-assemblage des chaînes atomiques sur la surface de Si(111). Ces nanostructures ont suscité un énorme intérêt en raison de leurs propriétés électroniques quasi uni-dimensionnelles. En se basant sur la combinaison de nos études STM et LEED, nous proposons un nouveau modèle structural pour les chaînes atomiques induites par le Gd. Nous concluons qu'outre les adsorbats mono- et divalents, les adsorbats trivalents sont aussi capables de stabiliser des chaînes atomiques. Ceci établit les chaînes constituées de silicium du type "honeycomb" et "Seiwatz" comme blocs de construction universels dans les reconstructions de chaîne atomiques induites par les adsorbats. La systèmatique dans l'auto-assemblage est expliquée en reliant l'état de valence de l'adsorbat aux symétries accessibles des chaînes. Nous examinons encore théoriquement la stabilité des différentes phases de chaînes en utilisant des méthodes de calculs de structure électronique "ab initio" et comparons nos résultats aux expériences. Advisors/Committee Members: Philipp (Dir.).

Subjects/Keywords: density functional theory

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APA (6^th Edition):

Battaglia, C. (2008). Structural and electronic properties of self-assembled nanostructures on silicon surfaces. (Thesis). Université de Neuchâtel. Retrieved from http://doc.rero.ch/record/9568

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):

Battaglia, Corsin. “Structural and electronic properties of self-assembled nanostructures on silicon surfaces.” 2008. Thesis, Université de Neuchâtel. Accessed February 27, 2021. http://doc.rero.ch/record/9568.

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

MLA Handbook (7^th Edition):

Battaglia, Corsin. “Structural and electronic properties of self-assembled nanostructures on silicon surfaces.” 2008. Web. 27 Feb 2021.

Vancouver:

Battaglia C. Structural and electronic properties of self-assembled nanostructures on silicon surfaces. [Internet] [Thesis]. Université de Neuchâtel; 2008. [cited 2021 Feb 27]. Available from: http://doc.rero.ch/record/9568.

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

Council of Science Editors:

Battaglia C. Structural and electronic properties of self-assembled nanostructures on silicon surfaces. [Thesis]. Université de Neuchâtel; 2008. Available from: http://doc.rero.ch/record/9568

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

University of Manitoba

18. Singh, Simarpreet. Computational investigations of reactivity and selectivity in addition reactions.

Degree: Chemistry, 2018, University of Manitoba

URL: http://hdl.handle.net/1993/33677

► The development and application of density functional theory (DFT) on real chemical systems has allowed experimentalists to use computational chemistry, without an understanding of mathematical… (more)

Subjects/Keywords: Density Functional Theory; Organocatalysis; Asymmetric Synthesis

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APA (6^th Edition):

Singh, S. (2018). Computational investigations of reactivity and selectivity in addition reactions. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/33677

Chicago Manual of Style (16^th Edition):

Singh, Simarpreet. “Computational investigations of reactivity and selectivity in addition reactions.” 2018. Masters Thesis, University of Manitoba. Accessed February 27, 2021. http://hdl.handle.net/1993/33677.

MLA Handbook (7^th Edition):

Singh, Simarpreet. “Computational investigations of reactivity and selectivity in addition reactions.” 2018. Web. 27 Feb 2021.

Vancouver:

Singh S. Computational investigations of reactivity and selectivity in addition reactions. [Internet] [Masters thesis]. University of Manitoba; 2018. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1993/33677.

Council of Science Editors:

Singh S. Computational investigations of reactivity and selectivity in addition reactions. [Masters Thesis]. University of Manitoba; 2018. Available from: http://hdl.handle.net/1993/33677

Rice University

19. Zhang, Yuchong. Thermodynamic Modeling of Branched Molecular Systems.

Degree: PhD, Engineering, 2019, Rice University

URL: http://hdl.handle.net/1911/106015

► Presence of branches in the molecular structure results in properties different from that of linear molecules and also leads to special industrial value and diverse… (more)

Subjects/Keywords: Thermodynamics; Branched Molecules; SAFT; Density Functional Theory

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APA (6^th Edition):

Zhang, Y. (2019). Thermodynamic Modeling of Branched Molecular Systems. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/106015

Chicago Manual of Style (16^th Edition):

Zhang, Yuchong. “Thermodynamic Modeling of Branched Molecular Systems.” 2019. Doctoral Dissertation, Rice University. Accessed February 27, 2021. http://hdl.handle.net/1911/106015.

MLA Handbook (7^th Edition):

Zhang, Yuchong. “Thermodynamic Modeling of Branched Molecular Systems.” 2019. Web. 27 Feb 2021.

Vancouver:

Zhang Y. Thermodynamic Modeling of Branched Molecular Systems. [Internet] [Doctoral dissertation]. Rice University; 2019. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1911/106015.

Council of Science Editors:

Zhang Y. Thermodynamic Modeling of Branched Molecular Systems. [Doctoral Dissertation]. Rice University; 2019. Available from: http://hdl.handle.net/1911/106015

Victoria University of Wellington

20. Leeb, Nina. Tracking the Source of Enantioselectivity.

Degree: 2015, Victoria University of Wellington

URL: http://hdl.handle.net/10063/4906

► Enantioselectivity remains one of synthetic chemistry’s most formidable problems. It arises due to the formation of diastereomeric species in a reaction, either in the form… (more)

▼ Enantioselectivity remains one of synthetic chemistry’s most formidable problems. It arises due to the formation of diastereomeric species in a reaction, either in the form of diastereomeric intermediates or a set of diastereomeric transition states. Without control a racemic mixture is formed. A resolution method is then required to separate the enantiomers. Any given resolution method will rely on the differing energies of diastereomers to allow for their separation. Experimentally there are a myriad of different options that may be used to induce separation; for example chromatography and/or crystallisation. The actual process that occurs through- out this separation has not, however, been fully investigated in all cases. A better understanding of the process is able to provide an understanding of how resolution methods work i.e. when diastereomers occur and how great their energy differences are. This is vital in increasing the efficiency and effectiveness of any given resolution method. This theoretical study completed an investigation of the reaction pathway between the enantiomers of 2-formyl-3-hydroxyl[2.2]paracyclophane (FHPC) with (S)-valyl-(S)-valine. A subsequent investigation of an alternative resolution method, involving (R)-α-PEAM, was also conducted. This latter resolution method was proposed experimentally as a simpler method that could aid in improving the separation of the enantiomers. This investigation was carried out using Density Functional Theory (DFT) with the PBE0 functional and the triple-ζ TZVP basis set. The complete reaction profile was determined and diastereomeric intermediates and transition states for both resolution methods along two different pathways were determined; the ‘N-deprotonation Pathway’ and the ‘O-deprotonation Pathway’. The inadequacy of the first resolution method was found to be due to the presence of copper(II). Furthermore it was discovered that the re- action for both pathways would most likely proceed through the ‘O-deprotonation Pathway’ due to the barriers being lower in energy. Advisors/Committee Members: Lein, Matthias.

Subjects/Keywords: DFT; Chiral resolution; Cyclophane; Density Functional Theory

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

APA (6^th Edition):

Leeb, N. (2015). Tracking the Source of Enantioselectivity. (Masters Thesis). Victoria University of Wellington. Retrieved from http://hdl.handle.net/10063/4906

Chicago Manual of Style (16^th Edition):

Leeb, Nina. “Tracking the Source of Enantioselectivity.” 2015. Masters Thesis, Victoria University of Wellington. Accessed February 27, 2021. http://hdl.handle.net/10063/4906.

MLA Handbook (7^th Edition):

Leeb, Nina. “Tracking the Source of Enantioselectivity.” 2015. Web. 27 Feb 2021.

Vancouver:

Leeb N. Tracking the Source of Enantioselectivity. [Internet] [Masters thesis]. Victoria University of Wellington; 2015. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10063/4906.

Council of Science Editors:

Leeb N. Tracking the Source of Enantioselectivity. [Masters Thesis]. Victoria University of Wellington; 2015. Available from: http://hdl.handle.net/10063/4906

Virginia Tech

21. Li, Zheng. Accelerating Catalyst Discovery via Ab Initio Machine Learning.

Degree: PhD, Chemical Engineering, 2019, Virginia Tech

URL: http://hdl.handle.net/10919/95915

► Machine learning and deep learning techniques have revolutionized a range of industries in recent years and have huge potential to improve every aspect of our… (more)

▼ Machine learning and deep learning techniques have revolutionized a range of industries in recent years and have huge potential to improve every aspect of our daily lives. Essentially, machine-learning provides algorithms the ability to automatically discover the hidden patterns of data without being explicitly programmed. Because of this, machine learning models have gained huge successes in applications such as website recommendation systems, online fraud detection, robotic technologies, image recognition, etc. Nevertheless, implementing machine-learning techniques in the field of catalyst design remains difficult due to 2 primary challenges. The first challenge is our insufficient knowledge about the structure-property relationships for diverse material systems. Typically, developing a physically intuitive material feature method requests in-depth expert knowledge about the underlying physics of the material system and it is always an active field. The second challenge is the lack of training data in academic research. In many cases, collecting a sufficient amount of training data is not always feasible due to the limitation of computational/experimental resources. Subsequently, the machine learning model optimized with small data tends to be over-fitted and could provide biased predictions with huge uncertainties. To address the above-mentioned challenges, this thesis focus on the development of robust feature methods and strategies for a variety of catalyst systems using the density functional theory (DFT) calculations. Through the case studies in the chapters, we show that the bulk electronic structure characteristics are successful features for capturing the adsorption properties of metal alloys and metal oxides. While molecular graphs are robust features for the molecular property, e.g., energy gap, of metal-organics compounds. Besides, we demonstrate that the adaptive machine learning workflow is an effective strategy to tackle the data deficiency issue in search of perovskite catalysts for the oxygen evolution reaction. Advisors/Committee Members: Xin, Hongliang (committeechair), Achenie, Luke E. K. (committeechair), Deshmukh, Sanket A. (committee member), Morris, Amanda (committee member).

Subjects/Keywords: Computational catalysis; Density functional theory; Machine learning

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APA (6^th Edition):

Li, Z. (2019). Accelerating Catalyst Discovery via Ab Initio Machine Learning. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/95915

Chicago Manual of Style (16^th Edition):

Li, Zheng. “Accelerating Catalyst Discovery via Ab Initio Machine Learning.” 2019. Doctoral Dissertation, Virginia Tech. Accessed February 27, 2021. http://hdl.handle.net/10919/95915.

MLA Handbook (7^th Edition):

Li, Zheng. “Accelerating Catalyst Discovery via Ab Initio Machine Learning.” 2019. Web. 27 Feb 2021.

Vancouver:

Li Z. Accelerating Catalyst Discovery via Ab Initio Machine Learning. [Internet] [Doctoral dissertation]. Virginia Tech; 2019. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10919/95915.

Council of Science Editors:

Li Z. Accelerating Catalyst Discovery via Ab Initio Machine Learning. [Doctoral Dissertation]. Virginia Tech; 2019. Available from: http://hdl.handle.net/10919/95915

University of New Mexico

22. Johnson, Ryan. Theoretical Studies of Transition Metal Catalysis.

Degree: Department of Chemistry and Chemical Biology, 2014, University of New Mexico

URL: https://digitalrepository.unm.edu/chem_etds/38

► Transition metal catalysis, being critical to nearly all aspects of the modern industrial world, is the focus of a series of theoretical studies which seek… (more)

Subjects/Keywords: Catalysis; Transition metals; Density functional theory

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APA (6^th Edition):

Johnson, R. (2014). Theoretical Studies of Transition Metal Catalysis. (Doctoral Dissertation). University of New Mexico. Retrieved from https://digitalrepository.unm.edu/chem_etds/38

Chicago Manual of Style (16^th Edition):

Johnson, Ryan. “Theoretical Studies of Transition Metal Catalysis.” 2014. Doctoral Dissertation, University of New Mexico. Accessed February 27, 2021. https://digitalrepository.unm.edu/chem_etds/38.

MLA Handbook (7^th Edition):

Johnson, Ryan. “Theoretical Studies of Transition Metal Catalysis.” 2014. Web. 27 Feb 2021.

Vancouver:

Johnson R. Theoretical Studies of Transition Metal Catalysis. [Internet] [Doctoral dissertation]. University of New Mexico; 2014. [cited 2021 Feb 27]. Available from: https://digitalrepository.unm.edu/chem_etds/38.

Council of Science Editors:

Johnson R. Theoretical Studies of Transition Metal Catalysis. [Doctoral Dissertation]. University of New Mexico; 2014. Available from: https://digitalrepository.unm.edu/chem_etds/38

University of Minnesota

23. Marell, Daniel. Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory.

Degree: PhD, Chemistry, 2016, University of Minnesota

URL: http://hdl.handle.net/11299/182795

► The application of computational chemistry has a wide scope of utility. From large systems such as proteins or metal-organic frameworks down to the understanding of… (more)

▼ The application of computational chemistry has a wide scope of utility. From large systems such as proteins or metal-organic frameworks down to the understanding of individual bonding patterns between atoms, there are endless opportunities to explore. Further utility is gained when the insights and resources of computational chemists can be applied to systems under investigation by experimental chemists The combined information of computational details with experimental findings can lead to new understanding of the systems being investigated. The ring-opening transesterification polymerization of caprolactone with an aluminum- salen catalyst is a useful reaction for the conversion of caprolactone to polyester. Mechanistic understanding of this reaction was gained through the interrogation of this process with density functional theory. Further, the origins for rate-enhancement through modification of electron-withdrawing groups was explained through the analysis of partial atomic charges. A rate enhancement observed by altering the backbone of the catalyst was also explained through the development of a distortion framework analysis. Rieske oxygenase are a class of protein that executes a variety of chemical reactions such as oxygenations, O- and N-demethylations, oxidations, and C–C bond formations en route to the formation of medically relevant natural products. The continued elucidation of the mechanism, including the characterization of reactive species was persued. Computational work to understand the impact partial atomic charge on the aromatic system (by inclusion of fluorine substituents) had on the rate constant demonstrated a clear correlation between the partial atomic charge on the C(2) position and the rate constant for a variety of substrates. A new reaction, the hexadehydro-Diels–Alder (HDDA) reaction takes a diyne and a diynophile to create a reactive benzyne intermediate. A series of six intramolecular HDDA substrates were found to undergo this transformation at relatively similar rates. Analysis of transition state geometries, investigation of both closed-shell and diradical mechanistic pathways, as well as insight from high-level calculations provide information about the nature of this intramolecular reaction. Extension of the mechanism led to predictive capability in good agreement with a new set of substrates as well.

Subjects/Keywords: density-functional theory; polymerization; reaction mechanism

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APA (6^th Edition):

Marell, D. (2016). Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/182795

Chicago Manual of Style (16^th Edition):

Marell, Daniel. “Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory.” 2016. Doctoral Dissertation, University of Minnesota. Accessed February 27, 2021. http://hdl.handle.net/11299/182795.

MLA Handbook (7^th Edition):

Marell, Daniel. “Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory.” 2016. Web. 27 Feb 2021.

Vancouver:

Marell D. Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory. [Internet] [Doctoral dissertation]. University of Minnesota; 2016. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/11299/182795.

Council of Science Editors:

Marell D. Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory. [Doctoral Dissertation]. University of Minnesota; 2016. Available from: http://hdl.handle.net/11299/182795

Virginia Tech

24. Fuhrer, Timothy J. Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes.

Degree: PhD, Chemistry, 2013, Virginia Tech

URL: http://hdl.handle.net/10919/19344

► The chemistry of fullerenes, which are a class of carbon allotropes that can be prepared by vaporization of graphite in an electric arc in a… (more)

Subjects/Keywords: Fullerenes; Endohedral; Metallofullerenes; Density Functional Theory

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APA (6^th Edition):

Fuhrer, T. J. (2013). Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/19344

Chicago Manual of Style (16^th Edition):

Fuhrer, Timothy J. “Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes.” 2013. Doctoral Dissertation, Virginia Tech. Accessed February 27, 2021. http://hdl.handle.net/10919/19344.

MLA Handbook (7^th Edition):

Fuhrer, Timothy J. “Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes.” 2013. Web. 27 Feb 2021.

Vancouver:

Fuhrer TJ. Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes. [Internet] [Doctoral dissertation]. Virginia Tech; 2013. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10919/19344.

Council of Science Editors:

Fuhrer TJ. Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes. [Doctoral Dissertation]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/19344

Virginia Tech

25. Li, Zheng. Assessing Structure–Property Relationships of Crystal Materials using Deep Learning.

Degree: MS, Computer Science and Applications, 2020, Virginia Tech

URL: http://hdl.handle.net/10919/99488

► Machine learning technologies, particularly deep learning, have demonstrated remarkable progress in facilitating the high-throughput materials discovery process. In essence, machine learning algorithms have the ability… (more)

Subjects/Keywords: Density functional theory; Material design; Machine learning

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APA (6^th Edition):

Li, Z. (2020). Assessing Structure–Property Relationships of Crystal Materials using Deep Learning. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/99488

Chicago Manual of Style (16^th Edition):

Li, Zheng. “Assessing Structure–Property Relationships of Crystal Materials using Deep Learning.” 2020. Masters Thesis, Virginia Tech. Accessed February 27, 2021. http://hdl.handle.net/10919/99488.

MLA Handbook (7^th Edition):

Li, Zheng. “Assessing Structure–Property Relationships of Crystal Materials using Deep Learning.” 2020. Web. 27 Feb 2021.

Vancouver:

Li Z. Assessing Structure–Property Relationships of Crystal Materials using Deep Learning. [Internet] [Masters thesis]. Virginia Tech; 2020. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10919/99488.

Council of Science Editors:

Li Z. Assessing Structure–Property Relationships of Crystal Materials using Deep Learning. [Masters Thesis]. Virginia Tech; 2020. Available from: http://hdl.handle.net/10919/99488

University of Texas – Austin

26. Li, Xinyu, Ph. D. Computational investigation of functional perovskites.

Degree: PhD, Materials Science & Engineering, 2018, University of Texas – Austin

URL: http://hdl.handle.net/2152/67995

► Functional perovskites have been investigated extensively for many years. Thousands of new perovskites are synthesized and studied every year. Many functional perovskites have been widely… (more)

▼ Functional perovskites have been investigated extensively for many years. Thousands of new perovskites are synthesized and studied every year. Many functional perovskites have been widely employed in industry. Density functional theory (DFT) calculations have been used to obtain a better understanding of functional perovskites, especially their electronic and structural properties. During my graduate study, I investigated perovskite’s properties on ionic transport, magnetic ordering, ferroelectricity, physical property and phase transition using DFT calculations. In the first case, I simulated the ionic transport process in several Ruddlesden- Popper (RP) phases. Climbing image nudged elastic band (CI-NEB) calculation was used to get accurate oxygen interstitial migration barrier. I established a linkage between interstitial migration barrier and perovskite’s octahedral rotation with symmetry mode approach. Two factors, including A-site atom radius and epitaxial strain, were used to reduce interstitial migration barrier in my simulation. My study on ionic transport in RP phases provides guidance on the design of fast ionic transport in perovskite oxides. In the second case, DFT calculation was employed to investigate a double perovskite’s magnetic and electronic properties. A new ferroelectric mechanism in perovskite, associated with the displacement of coplanar Mn²⁺, was discovered experimentally. My DFT calculation explained the origin of coplanar displacement from an orbital point of view. In addition, DFT simulations were used in the design of ferroelectricity enhancement perovskite. In the last case, I simulated structural behaviors under pressure of several double perovskites. The results show that these double perovskites can be divided into two groups based on their octahedral rotations under pressure. The origin of their distinct volume reduction mechanisms was studied through DFT simulations. The difference between the two mechanisms and their influence on bulk modulus were discussed based on my computational results. Advisors/Committee Members: Henkelman, Graeme (advisor), Zhou, Jianshi (advisor), Goodenough, John (committee member), Hwang, Gyeong (committee member).

Subjects/Keywords: First-principle calculation; Density functional theory; Perovskite

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APA (6^th Edition):

Li, Xinyu, P. D. (2018). Computational investigation of functional perovskites. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/67995

Chicago Manual of Style (16^th Edition):

Li, Xinyu, Ph D. “Computational investigation of functional perovskites.” 2018. Doctoral Dissertation, University of Texas – Austin. Accessed February 27, 2021. http://hdl.handle.net/2152/67995.

MLA Handbook (7^th Edition):

Li, Xinyu, Ph D. “Computational investigation of functional perovskites.” 2018. Web. 27 Feb 2021.

Vancouver:

Li, Xinyu PD. Computational investigation of functional perovskites. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2018. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/2152/67995.

Council of Science Editors:

Li, Xinyu PD. Computational investigation of functional perovskites. [Doctoral Dissertation]. University of Texas – Austin; 2018. Available from: http://hdl.handle.net/2152/67995

University of Texas – Austin

27. Li, Hao, Ph. D. Catalytic reactions at alloy surfaces.

Degree: PhD, Chemistry, 2020, University of Texas – Austin

URL: http://dx.doi.org/10.26153/tsw/8356

► Alloys have been widely studied for heterogeneous catalysis. Many bi- and multi-metallic alloys have enhanced performance as compared to their monometallic counterparts. However, a full… (more)

Subjects/Keywords: Catalysis; Alloy; Density functional theory; Catalytic modeling

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APA (6^th Edition):

Li, Hao, P. D. (2020). Catalytic reactions at alloy surfaces. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://dx.doi.org/10.26153/tsw/8356

Chicago Manual of Style (16^th Edition):

Li, Hao, Ph D. “Catalytic reactions at alloy surfaces.” 2020. Doctoral Dissertation, University of Texas – Austin. Accessed February 27, 2021. http://dx.doi.org/10.26153/tsw/8356.

MLA Handbook (7^th Edition):

Li, Hao, Ph D. “Catalytic reactions at alloy surfaces.” 2020. Web. 27 Feb 2021.

Vancouver:

Li, Hao PD. Catalytic reactions at alloy surfaces. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2020. [cited 2021 Feb 27]. Available from: http://dx.doi.org/10.26153/tsw/8356.

Council of Science Editors:

Li, Hao PD. Catalytic reactions at alloy surfaces. [Doctoral Dissertation]. University of Texas – Austin; 2020. Available from: http://dx.doi.org/10.26153/tsw/8356

University of Texas – Austin

28. -6008-5857. Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications.

Degree: PhD, Electrical and Computer engineering, 2016, University of Texas – Austin

URL: http://hdl.handle.net/2152/40264

► End-of-the-roadmap CMOS devices are explored via particle-based ensemble semi-classical Monte Carlo (MC) methods employing quantum corrections (QCs) to address quantum confinement and degenerate carrier populations.… (more)

▼ End-of-the-roadmap CMOS devices are explored via particle-based ensemble semi-classical Monte Carlo (MC) methods employing quantum corrections (QCs) to address quantum confinement and degenerate carrier populations. The significance of such QCs is illustrated through simulation of n-channel III-V and Si FinFETs. Original contributions include our treatment of far-from-equilibrium degenerate statistics and QC-based modeling of surface-roughness scattering, as well as considering quantum-confined phonon and ionized-impurity scattering in 3D. Typical MC simulations approximate degenerate carrier populations as Fermi distributions to model the Pauli-blocking (PB) of scattering to occupied final states. To allow for increasingly far-from-equilibrium non-Fermi carrier distributions in ultra-scaled and III-V devices, we instead generate the final-state occupation probabilities used for PB by sampling the local carrier populations as a function of energy and energy valley. This process is aided by the use of fractional carriers or sub-carriers, which minimizes classical carrier-carrier scattering. Quantum confinement effects are addressed through quantum-correction potentials (QCPs) generated from coupled Schrödinger-Poisson solvers, as commonly done. However, we use our valley- and orientation-dependent QCPs not just to redistribute carriers in real space, or even among energy valleys, but also to calculate confinement-dependent phonon, ionized-impurity, and surface-roughness scattering rates. Collectively, these quantum effects can substantially reduce and even eliminate otherwise expected benefits of considered InGaAs FinFETs over otherwise identical Si FinFETs, despite higher thermal velocities in InGaAs. Beyond-CMOS device concepts are also being considered for future applications. Thin-film sub-5 nm magnetic skyrmions constitute an ultimate scaling alternative for beyond-CMOS data storage technologies. These robust non-collinear spin-textures can be moved and manipulated by spin-polarized or non-spin-polarized electrical currents, which is extremely attractive for integration with current memory technologies. An innovative technique to detect isolated nano-skyrmions with a current-perpendicular-to-plane is shown, which has immediate implications for device concepts. Such a mechanism is explored by studying the atomistic electronic structure of the magnetic quasiparticles. The tunneling conductance is quite sensitive to spatial variations in the electronic structure, as a large atomistic conductance anisotropy up to 20 is found for magnetic skyrmions in Pd/Fe/Ir(111) magnetic thin-films. This spin-mixing magnetoresistance effect possibly could be incorporated in future magnetic storage technologies. Advisors/Committee Members: Register, Leonard F. (advisor), Banerjee, Sanjay K (committee member), Tutuc, Emanuel (committee member), Lee, Jack C (committee member), MacDonald, Allan H (committee member).

Subjects/Keywords: FinFETs; Skyrmions; Monte Carlo; Density-functional theory

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APA (6^th Edition):

-6008-5857. (2016). Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/40264

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Chicago Manual of Style (16^th Edition):

-6008-5857. “Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications.” 2016. Doctoral Dissertation, University of Texas – Austin. Accessed February 27, 2021. http://hdl.handle.net/2152/40264.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

-6008-5857. “Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications.” 2016. Web. 27 Feb 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

-6008-5857. Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2016. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/2152/40264.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

-6008-5857. Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications. [Doctoral Dissertation]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/40264

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

University of Oklahoma

29. Mou, Tong. Thermocatalytic and Plasmonic Catalytic Hydrogenation Reactions from First Principles.

Degree: PhD, 2020, University of Oklahoma

URL: http://hdl.handle.net/11244/324960

► As the world is facing post-climate change situation and the escalating demand of energy, a gradual energy transition from fossil fuels (oil, coal, natural gas)… (more)

▼ As the world is facing post-climate change situation and the escalating demand of energy, a gradual energy transition from fossil fuels (oil, coal, natural gas) to renewable energy technologies (natural resources such as biomass, solar, wind) is inevitable and essential. Solar energy, as the most abundant, safe and clean energy source among all available renewable energy technologies, has prospective potentials as future power generators. However, although significant progress has been made, the electricity generation from sunlight in commercial photovoltaic (PV) solar cells still suffer from low energy conversion efficiency and high cost. In addition, due to technological difficulties associated with the rapid electron-hole recombination in photocatalysis systems, realizing commercial implementations of photocatalytic systems remains a challenge. In this dissertation, a thorough first-principles analysis was performed on three hydrogen-involving processes, including solar to electricity, catalytic hydrotreating and solar to chemical conversion processes. By investigating their thermodynamic and kinetics properties, we aim to bridge solar energy utilization with chemical energy production under ambient conditions. We begin with the discussion of nitrogen-related defects in a dilute nitride material GaInNAs, which shows promising candidacy as the fourth junction in multijunction solar cells. While the photoluminescence spectra presented remaining defects in the hydrogenated alloy, first-principles calculations revealed the thermodynamic limitation of hydrogen addition on the In-N complexes. Next, a comprehensive kinetic study on cyclohexene hydrogenation reaction on palladium and palladium hydride surfaces were conducted, through a combination of experimental and theoretical work, which laid foundations for later study of plasmonic hydrogenation reactions. In light of thermodynamic and kinetic studies addressed earlier, we undertake investigations on plasmonic catalytic hydrogenation of 4-nitrophenol on gold surfaces. We measured the catalytic activity with and without light irradiation and observed higher reaction rates under light. A theoretical correlation between rate enhancements and reaction energy barrier reduction was constructed via density functional theory calculations. Moreover, we propose that the reaction can be further enhanced over a hexagonal boron nitride (h-BN) layer supported on Au in an [email protected] core-shell structure. In this dissertation, we attempt to understand the electron behavior at atomic level, through the investigation of hydrogen-involved processes. Moreover, by discussing efficiency improvement options, we attempt to guide the future design of plasmonic catalysts. Advisors/Committee Members: Wang, Bin (advisor), Sellers, Ian (committee member), Resasco, Daniel (committee member), Huang, Liangliang (committee member), Walters, Keisha (committee member).

Subjects/Keywords: Density Functional Theory; hydrogenation; plasmonic catalysis

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APA (6^th Edition):

Mou, T. (2020). Thermocatalytic and Plasmonic Catalytic Hydrogenation Reactions from First Principles. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/324960

Chicago Manual of Style (16^th Edition):

Mou, Tong. “Thermocatalytic and Plasmonic Catalytic Hydrogenation Reactions from First Principles.” 2020. Doctoral Dissertation, University of Oklahoma. Accessed February 27, 2021. http://hdl.handle.net/11244/324960.

MLA Handbook (7^th Edition):

Mou, Tong. “Thermocatalytic and Plasmonic Catalytic Hydrogenation Reactions from First Principles.” 2020. Web. 27 Feb 2021.

Vancouver:

Mou T. Thermocatalytic and Plasmonic Catalytic Hydrogenation Reactions from First Principles. [Internet] [Doctoral dissertation]. University of Oklahoma; 2020. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/11244/324960.

Council of Science Editors:

Mou T. Thermocatalytic and Plasmonic Catalytic Hydrogenation Reactions from First Principles. [Doctoral Dissertation]. University of Oklahoma; 2020. Available from: http://hdl.handle.net/11244/324960

University of Toledo

30. Shi, Tingting. Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations.

Degree: PhD, College of Natural Sciences and Mathematics, 2014, University of Toledo

URL: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935

► In this dissertation, a series of earth-abundant photovoltaic materials including lead halide perovskites, copper based compounds, and silicon are investigated via density functional theory (DFT).… (more)

▼ In this dissertation, a series of earth-abundant photovoltaic materials including lead halide perovskites, copper based compounds, and silicon are investigated via density functional theory (DFT). Firstly, we study the unique optoelectronic properties of perovskite CH3NH3PbI3 and CH3NH3PbBr3. First-principle calculations show that CH3NH3PbI3 perovskite solar cells exhibit remarkable optoelectronic properties that account for the high open circuit voltage (Voc) and long electron-hole diffusion lengths. Our results reveal that for intrinsic doping, dominant point defects produce only shallow levels. Therefore lead halide perovskites are expected to exhibit intrinsic low non-radiative recombination rates. The conductivity of perovskites can be tuned from p-type to n-type by controlling the growth conditions. For extrinsic defects, the p-type perovskites can be achieved by doping group-IA, -IB, or -VIA elements, such as Na, K, Rb, Cu, and O at I-rich growth conditions. We further show that despite a large band gap of 2.2 eV, the dominant defects in CH3NH3PbBr3 also create only shallow levels. The photovoltaic properties of CH3NH3PbBr3–based perovskite absorbers can be tuned via defect engineering. Highly conductive p-type CH3NH3PbBr3 can be synthesized under Br-rich growth conditions. Such CH3NH3PbBr3 may be potential low-cost hole transporting materials for lead halide perovskite solar cells. All these unique defect properties of perovskites are largely due to the strong Pb lone-pair s orbital and I p (Br p) orbital antibonding coupling and the high ionicity of CH3NH3PbX3 (X=I, Br). Secondly, we study the optoelectronic properties of Cu-V-VI earth abundant compounds. These low cost thin films may have the good electronic and optical properties. We have studied the structural, electronic and optical properties of Cu3-V-VI4 compounds. After testing four different crystal structures, enargite, wurtzite-PMCA, famatinite and zinc-blend-PMCA, we find that Cu3PS4 and Cu3PSe4 prefer energetically the enargite structure, whereas, other compounds favor the famatinite structure. Among the compounds and structures considered, enargite Cu3PSe4, and famatinite Cu3AsS4, are suitable for single junction solar cell applications due to bandgaps of 1.32 eV and 1.15 eV, respectively. Furthermore, CuSbS2 are also studied by density functional theory and HSE06 hybrid functional. The chalcostibite CuSbS2 has an indirect band gap of 1.85 eV, whereas the chalcogenide Cu3SbS4 has a direct band gap of 0.89 eV. We find that the large difference on band gaps is mainly attributed to the different Sb charge states. We further predict that the Sb charge states will affect the defect physics. Particularly, the Sb lone pair s orbitals in CuSbS2 have strong influence on the formation energies of Sb-related defects. Lastly, we have studied the atomic structure and electronic properties of aluminum (Al)-related defect complexes in silicon. We find a unique stable complex configuration consisting of an Ali and an oxygen dimer, Ali-2Oi, which introduces deep… Advisors/Committee Members: Yan, Yanfa (Advisor).

Subjects/Keywords: Physics; Perovskites solar cell, Density functional theory

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

APA (6^th Edition):

Shi, T. (2014). Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations. (Doctoral Dissertation). University of Toledo. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935

Chicago Manual of Style (16^th Edition):

Shi, Tingting. “Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations.” 2014. Doctoral Dissertation, University of Toledo. Accessed February 27, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935.

MLA Handbook (7^th Edition):

Shi, Tingting. “Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations.” 2014. Web. 27 Feb 2021.

Vancouver:

Shi T. Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations. [Internet] [Doctoral dissertation]. University of Toledo; 2014. [cited 2021 Feb 27]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935.

Council of Science Editors:

Shi T. Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations. [Doctoral Dissertation]. University of Toledo; 2014. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935

Open Access Theses and Dissertations