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Georgia Tech
1.
Freeman, Gary Michael.
Preparative, structural and electrochemical studies of metal complexes of N-alkylated cyclam ligands.
Degree: PhD, Chemistry, 1983, Georgia Tech
URL: http://hdl.handle.net/1853/30277 
Subjects/Keywords: Electrochemical analysis; Ligands
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APA (6th Edition):
Freeman, G. M. (1983). Preparative, structural and electrochemical studies of metal complexes of N-alkylated cyclam ligands. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/30277
Chicago Manual of Style (16th Edition):
Freeman, Gary Michael. “Preparative, structural and electrochemical studies of metal complexes of N-alkylated cyclam ligands.” 1983. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/30277.
MLA Handbook (7th Edition):
Freeman, Gary Michael. “Preparative, structural and electrochemical studies of metal complexes of N-alkylated cyclam ligands.” 1983. Web. 16 Jan 2021.
Vancouver:
Freeman GM. Preparative, structural and electrochemical studies of metal complexes of N-alkylated cyclam ligands. [Internet] [Doctoral dissertation]. Georgia Tech; 1983. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/30277.
Council of Science Editors:
Freeman GM. Preparative, structural and electrochemical studies of metal complexes of N-alkylated cyclam ligands. [Doctoral Dissertation]. Georgia Tech; 1983. Available from: http://hdl.handle.net/1853/30277
Georgia Tech
2.
Carrier, Allen Mark.
Some organometallic chemistry of iminium and nitrilium salts.
Degree: PhD, Chemistry, 1981, Georgia Tech
URL: http://hdl.handle.net/1853/30436
Subjects/Keywords: Imines; Chemistry, Organic
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APA (6th Edition):
Carrier, A. M. (1981). Some organometallic chemistry of iminium and nitrilium salts. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/30436
Chicago Manual of Style (16th Edition):
Carrier, Allen Mark. “Some organometallic chemistry of iminium and nitrilium salts.” 1981. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/30436.
MLA Handbook (7th Edition):
Carrier, Allen Mark. “Some organometallic chemistry of iminium and nitrilium salts.” 1981. Web. 16 Jan 2021.
Vancouver:
Carrier AM. Some organometallic chemistry of iminium and nitrilium salts. [Internet] [Doctoral dissertation]. Georgia Tech; 1981. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/30436.
Council of Science Editors:
Carrier AM. Some organometallic chemistry of iminium and nitrilium salts. [Doctoral Dissertation]. Georgia Tech; 1981. Available from: http://hdl.handle.net/1853/30436
Georgia Tech
3.
McCarten, Paul.
Synthesis and reactivity of alpha-heteroaton substituted organoiron compounds.
Degree: PhD, Chemistry, 1988, Georgia Tech
URL: http://hdl.handle.net/1853/30503
Subjects/Keywords: Chemical reactions; Organic compounds Synthesis
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APA (6th Edition):
McCarten, P. (1988). Synthesis and reactivity of alpha-heteroaton substituted organoiron compounds. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/30503
Chicago Manual of Style (16th Edition):
McCarten, Paul. “Synthesis and reactivity of alpha-heteroaton substituted organoiron compounds.” 1988. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/30503.
MLA Handbook (7th Edition):
McCarten, Paul. “Synthesis and reactivity of alpha-heteroaton substituted organoiron compounds.” 1988. Web. 16 Jan 2021.
Vancouver:
McCarten P. Synthesis and reactivity of alpha-heteroaton substituted organoiron compounds. [Internet] [Doctoral dissertation]. Georgia Tech; 1988. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/30503.
Council of Science Editors:
McCarten P. Synthesis and reactivity of alpha-heteroaton substituted organoiron compounds. [Doctoral Dissertation]. Georgia Tech; 1988. Available from: http://hdl.handle.net/1853/30503
4.
Rolle, Clarence J.
Selective aerobic oxidations catalyzed by manganese(III) complexes using redox-active ligands.
Degree: PhD, Chemistry and Biochemistry, 2011, Georgia Tech
URL: http://hdl.handle.net/1853/42827
► Selective oxidations are important for the functionalization of compounds in organic synthesis and chemical industry. Using O2 as a terminal e- acceptor would be ideal…
(more)
▼ Selective oxidations are important for the functionalization of compounds in organic synthesis and chemical industry. Using O2 as a terminal e- acceptor would be ideal because it is cheap and environmentally friendly, but aerobic oxidations are often prone to unselective free radical autoxidation. Recently developed palladium catalysts use O2 as a selective multi-electron oxidant for various organic transformations. Although these methods are powerful and sophisticated, the lower cost of base metals makes them attractive as potential alternatives. The challenge is to develop methods for effecting multi-electron transformations at metals that typically prefer one electron changes. To this end, the development of manganese(III) complexes containing redox-active ligands as catalysts for selective oxidase-type oxidation of organic substrates was pursued. Bis(tetrabromocatecholato) manganese(III) complexes were shown to aerobically oxidize catechols to form quinones and H2O2. This reactivity was extended to other alcohol and amine substrates. In these reactions, the non-innocent tetrabromocatecholate ligands may impart a multi-electron character to the metal. To directly probe the intermediacy of ligand-centered radicals in catalytic turnover, a series of structurally similar manganese(III) complexes with aminophenol-derived ligands were prepared and characterized. The capacity of these ligands to undergo low-energy redox changes, allowed for isolation of an electron transfer series spanning two redox states without a change in oxidation state at the metal center. The ligand-centered redox events were a key feature in aerobic homocoupling of Grignard reagents.
Advisors/Committee Members: Jake Soper (Committee Chair), Angus Wilkinson (Committee Member), Christoph Fahrni (Committee Member), Christopher Jones (Committee Member), Kent Barefield (Committee Member).
Subjects/Keywords: Oxidation chemistry; Metal catalysts; Metalloenzymes; Manganese; Manganese catalysts; Oxidases; Oxidation
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APA (6th Edition):
Rolle, C. J. (2011). Selective aerobic oxidations catalyzed by manganese(III) complexes using redox-active ligands. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/42827
Chicago Manual of Style (16th Edition):
Rolle, Clarence J. “Selective aerobic oxidations catalyzed by manganese(III) complexes using redox-active ligands.” 2011. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/42827.
MLA Handbook (7th Edition):
Rolle, Clarence J. “Selective aerobic oxidations catalyzed by manganese(III) complexes using redox-active ligands.” 2011. Web. 16 Jan 2021.
Vancouver:
Rolle CJ. Selective aerobic oxidations catalyzed by manganese(III) complexes using redox-active ligands. [Internet] [Doctoral dissertation]. Georgia Tech; 2011. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/42827.
Council of Science Editors:
Rolle CJ. Selective aerobic oxidations catalyzed by manganese(III) complexes using redox-active ligands. [Doctoral Dissertation]. Georgia Tech; 2011. Available from: http://hdl.handle.net/1853/42827
5.
Lippert, Cameron A.
Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis.
Degree: PhD, Chemistry and Biochemistry, 2011, Georgia Tech
URL: http://hdl.handle.net/1853/41199
► The making and breaking of O-O bonds has implications ranging from artificial photosynthesis and water oxidation to the use of O₂ as a selective, green…
(more)
▼ The making and breaking of O-O bonds has implications ranging from artificial photosynthesis and water oxidation to the use of O₂ as a selective, green oxidant for transformations of small molecules. Oxidative generation of O₂ from coupling of two H₂O molecules remains challenging, and well defined systems that catalytically evolve O₂ are exceedingly rare. Recent theoretical studies have invoked metal oxyl radicals (L[subscript n]M=O*) containing a singly occupied M-O π-type orbital as precursors to O-O bond forming events in both biological and synthetic water oxidation catalysts. However, the lack of stable metal oxyl complexes makes it difficult to explore and understand this hypothesis. The activation of dioxygen (breaking of O-O bonds) to produce terminal metal oxos also remains a challenge. There is an inherent kinetic barrier to the spin-forbidden reactions of triplet dioxygen, and features that engender selective O₂ reduction are not easily transferable from system to system. The primary thrust of this thesis work has been to elaborate new methods to generate well-defined metal oxyl radicals for studies of their reactions in radical bond-forming reactions similar to the radical coupling hypothesis of water oxidation.
A library of >20 5- and 6-coordinate high-valent oxorhenium complexes containing redox-inert and redox-active ligands has been prepared. The complexes containing redox-active ligands have shown the ability for ligand-mediated radical coupling reactions. Mechanistic studies of bimetallic O₂ homolysis (the microscopic reverse of water oxidation) and nitroxyl radical deoxygenation at five-coordinate oxorhenium(V) reveal that, in both net 2e⁻ reactions, coupling to a redox-active ligand lowers the kinetic barrier to the reaction by facilitating formation and stabilization of 1e⁻ oxidized intermediates.
Coordinatively unsaturated high-valent oxorhenium complexes containing redox-active ligands direct bond-forming reactions towards the metal center. This is undesirable towards the goal of forming O-O bonds. To address this problem coordinatively saturated Re(V) and Re(VII) complexes were prepared. Oxidation of these species by chemical oxidants allowed for the isolation of "masked" oxyl species. These complexes showed reactivity towards Si and trityl radicals to produce new Si-O and C-O bonds, whereas their closed-shell congeners were inert. We have successfully developed a method for the preparation and isolation of "masked" oxyl radicals and shown their utility in ligand-mediated radical coupling reactions.
Advisors/Committee Members: Jake D. Soper (Committee Chair), Amgus Wilkinson (Committee Member), Chris Jones (Committee Member), Kent Barefield (Committee Member), Z. John Zhang (Committee Member).
Subjects/Keywords: Inorganic synthesis; Water oxidation; Artificial photosynthesis; Catalysis; Photosynthesis; Oxidation-reduction reaction; Chemical reactions; Inorganic compounds Synthesis; Photosynthesis Industrial applications; Oxidation-reduction reaction
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APA (6th Edition):
Lippert, C. A. (2011). Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/41199
Chicago Manual of Style (16th Edition):
Lippert, Cameron A. “Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis.” 2011. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/41199.
MLA Handbook (7th Edition):
Lippert, Cameron A. “Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis.” 2011. Web. 16 Jan 2021.
Vancouver:
Lippert CA. Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis. [Internet] [Doctoral dissertation]. Georgia Tech; 2011. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/41199.
Council of Science Editors:
Lippert CA. Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis. [Doctoral Dissertation]. Georgia Tech; 2011. Available from: http://hdl.handle.net/1853/41199
Georgia Tech
6.
Hawkes, Joshua Mahlon.
The Simulation and Study of Conditions Leading to Axial Offset Anomaly in Pressurized Water Reactors.
Degree: MS, Mechanical Engineering, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/7612
► Axial offset anomaly (AOA) in pressurized water reactors (PWR) refers to deviation of the measured neutron flux in the top half of the core from…
(more)
▼ Axial offset anomaly (AOA) in pressurized water reactors (PWR) refers to deviation of the measured neutron flux in the top half of the core from the predicted values. Among other difficulties, AOA reduces the shutdown margin, and may force the plant to reduce power output. AOA is believed to be caused by three related phenomena occurring in the core while operating at full power: sub-cooled nucleate boiling concentrated mainly in the upper half of the core, corrosion product deposition on the cladding surface (crud), and the deposition of boron within the porous crud layer in regions of vigorous sub-cooled boiling.
This study replicates the conditions within the PWR primary coolant; specifically, the temperature, pressure, peak surface heat flux, coolant velocity and water chemistry are simulated in order to produce prototypical crud on an electrically heated Zircaloy-4 test element. At the conclusion of each test run, the heated Zircaloy-4 test element is rapidly isolated from the coolant in order to trap any soluble boron species that may be present in the crud layer. The results of this investigation indicate that prototypical crud with significant boron deposition can be produced. The deposited boron compound has been determined to be lithium tetraborate (Li2B4O7). Comparative experiments have been run to determine the effect of coolant pH, concentration and type of additives, and duration of exposure on the thickness of the crud deposit. The data obtained in this investigation can be used to validate mechanistic models for crud deposition and AOA in pressurized water reactors.
Advisors/Committee Members: Dr. Said Abdel-Khalik (Committee Chair), Dr. Kent Barefield (Committee Member), Dr. Nolan Hertel (Committee Member).
Subjects/Keywords: Corrosion product deposition; Boron oxide; Nickel ferrite; Lithium tetraborate; Axial Offset Anomaly (AOA); Crud Induced Power Shift (CIPS); Pressurized Water Reactor (PWR)
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APA (6th Edition):
Hawkes, J. M. (2004). The Simulation and Study of Conditions Leading to Axial Offset Anomaly in Pressurized Water Reactors. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/7612
Chicago Manual of Style (16th Edition):
Hawkes, Joshua Mahlon. “The Simulation and Study of Conditions Leading to Axial Offset Anomaly in Pressurized Water Reactors.” 2004. Masters Thesis, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/7612.
MLA Handbook (7th Edition):
Hawkes, Joshua Mahlon. “The Simulation and Study of Conditions Leading to Axial Offset Anomaly in Pressurized Water Reactors.” 2004. Web. 16 Jan 2021.
Vancouver:
Hawkes JM. The Simulation and Study of Conditions Leading to Axial Offset Anomaly in Pressurized Water Reactors. [Internet] [Masters thesis]. Georgia Tech; 2004. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/7612.
Council of Science Editors:
Hawkes JM. The Simulation and Study of Conditions Leading to Axial Offset Anomaly in Pressurized Water Reactors. [Masters Thesis]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/7612
Georgia Tech
7.
Kutukcu, Mehmet Nuri.
Synthesis and Characterization of Low and Negative Thermal Expansion Materials.
Degree: MS, Chemistry and Biochemistry, 2005, Georgia Tech
URL: http://hdl.handle.net/1853/7636
► The preparation and thermophysical properties of some In(I), Ga(I) and Ag(I) substituted NZP type materials were explored. Many compositions with the NZP framework show low…
(more)
▼ The preparation and thermophysical properties of some In(I), Ga(I) and Ag(I) substituted NZP type materials were explored. Many compositions with the NZP framework show low and negative thermal expansion.
Previously reported material, GaZr2(PO4(3, transforms from one NZP related phase into another NZP type phase due to oxidation under air above 300 °C. In addition, it exhibits hysteresis under inert atmosphere; the cell parameters are different on heating and cooling cycles for a given temperature. The synthesis, and characterization of a new material, InZr2(PO4)3, is outlined. It crystallizes in space group R -3 c. In addition, as GaZr2(PO4)3, it oxidizes above 300 °C under air and exhibits hysteresis under inert atmosphere. Furthermore, the synthesis of AgTixZr2-x(PO4)3 solid solution compositions, their ion exchange characteristics with Ga(I) and their thermophysical properties are described. Thermal expansion anisotropy (the difference between a and c ) of the solid solutions decreases as the bigger ion, Zr4+, is substituted by the smaller one, Ti4+. Thermal expansion characteristics of GaZr2(PO4)3, InZr2(PO4)3 and AgZr2(PO4)3 are compared with MZr2(PO4)3 ( M = Li, Na, K, Rb, Cs). Ionic radii for Ga(I) and In(I) in a six coordinate oxygen environment were proposed.
Advisors/Committee Members: Dr. Angus P. Wilkinson (Committee Chair), Dr. E. Kent Barefield (Committee Member), Dr. Z. John Zhang (Committee Member).
Subjects/Keywords: Ion exchange; Thermal behavior; X-ray diffraction; Negative thermal expansion; Univalent Ga and In
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APA (6th Edition):
Kutukcu, M. N. (2005). Synthesis and Characterization of Low and Negative Thermal Expansion Materials. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/7636
Chicago Manual of Style (16th Edition):
Kutukcu, Mehmet Nuri. “Synthesis and Characterization of Low and Negative Thermal Expansion Materials.” 2005. Masters Thesis, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/7636.
MLA Handbook (7th Edition):
Kutukcu, Mehmet Nuri. “Synthesis and Characterization of Low and Negative Thermal Expansion Materials.” 2005. Web. 16 Jan 2021.
Vancouver:
Kutukcu MN. Synthesis and Characterization of Low and Negative Thermal Expansion Materials. [Internet] [Masters thesis]. Georgia Tech; 2005. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/7636.
Council of Science Editors:
Kutukcu MN. Synthesis and Characterization of Low and Negative Thermal Expansion Materials. [Masters Thesis]. Georgia Tech; 2005. Available from: http://hdl.handle.net/1853/7636
Georgia Tech
8.
Eichler, Jack Frederick.
Coordination Compounds Possessing Stannylamines: Synthesis, Characterization, and Application.
Degree: PhD, Chemistry and Biochemistry, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/4932
► The marriage of synthetic chemistry to materials science has been well documented in the last decade. The design, synthesis, and utilization of chemical precursors in…
(more)
▼ The marriage of synthetic chemistry to materials science has been well documented in the last decade. The design, synthesis, and utilization of chemical precursors in the MOCVD of electronic materials in particular has received a lot of attention in both academic and industrial circles. The maintenance of this symbiotic relationship is pursued in this work in the hope of discovering chemical forerunners for high-dielectric metal oxide materials. Specifically, it is of interest to isolate chemical precursors for ZTT, a recent entry into the field of high-k composites.
The primary theme of this dissertation is the exploration of the design and synthesis of molecular precursors that possess more than one of the cations found in the final ZTT film. The approach taken to obtain such precursors, referred to in this work as same-source precursors, is to investigate the implementation of the anionic stannylamine ligand, -N(SnMe3)2 in the preparation of heterometallic coordination complexes. The ultimate goal is to procure volatile, low molecular weight compounds that possess more than one of the metals found in ZTT (tin, titanium, and/or zirconium).
The reason for choosing stannylamine ligands is two-fold. First, as was alluded to above, such ligands might provide convenient access to heterometallic complexes possessing tin as one of the metal constituents. Second, since the coordination chemistry of stannyl amines is relatively unexplored compared to alkyl- and silylamine ligands, it is important from a fundamental standpoint to investigate the synthetic utility of this ligand type.
With this motivation in mind, the results reported here accomplishe two major objectives: 1) the synthesis and characterization of a variety of metal complexes coordinated by stannylamines and 2) the design, synthesis, and utilization of heterometallic precursors for use in the MOCVD of ZTT. Thus, in the course of a synthetic investigation towards the goal of same-source ZTT precursors for use in MOCVD processes, a number of metal coordination complexes possessing stannylamine ligands have been synthesized and fully characterized. Consequently, the library of known compounds containing these ligands has been significantly expanded and a novel route to volatile, heterobimetallic aminoalkoxide species has been developed.
Advisors/Committee Members: William S. Rees, Jr. (Committee Chair), Angus P. Wilkinson (Committee Member), Dennis W. Hess (Committee Member), E. Kent Barefield (Committee Member), Z. John Zhang (Committee Member).
Subjects/Keywords: Group 14 elements; Heterometallic amidoalkoxides; ZTT; MOCVD; Stannylamines
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APA (6th Edition):
Eichler, J. F. (2004). Coordination Compounds Possessing Stannylamines: Synthesis, Characterization, and Application. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/4932
Chicago Manual of Style (16th Edition):
Eichler, Jack Frederick. “Coordination Compounds Possessing Stannylamines: Synthesis, Characterization, and Application.” 2004. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/4932.
MLA Handbook (7th Edition):
Eichler, Jack Frederick. “Coordination Compounds Possessing Stannylamines: Synthesis, Characterization, and Application.” 2004. Web. 16 Jan 2021.
Vancouver:
Eichler JF. Coordination Compounds Possessing Stannylamines: Synthesis, Characterization, and Application. [Internet] [Doctoral dissertation]. Georgia Tech; 2004. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/4932.
Council of Science Editors:
Eichler JF. Coordination Compounds Possessing Stannylamines: Synthesis, Characterization, and Application. [Doctoral Dissertation]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/4932
Georgia Tech
9.
Richardson, John Michael.
Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons.
Degree: PhD, Chemical and Biomolecular Engineering, 2008, Georgia Tech
URL: http://hdl.handle.net/1853/22704
► This work focuses on understanding the heterogeneous/homogeneous nature of the catalytic species for a variety of immobilized metal precatalysts used for C-C coupling reactions. These…
(more)
▼ This work focuses on understanding the heterogeneous/homogeneous nature of the catalytic species for a variety of immobilized metal precatalysts used for C-C coupling reactions. These precatalysts include: (i) tethered organometallic palladium pincer complexes, (ii) an encapsulated small molecule palladium complex in a polymer matrix, (iii) mercapto-modified mesoporous silica metalated with palladium acetate, and (iv) amino-functionalized mesoporous silicas metalated with Ni(II). As part of this investigation, the use of metal scavengers as selective poisons of homogeneous catalysis is introduced and investigated as a test for distinguishing heterogeneous from homogeneous catalysis. The premise of this test is that insoluble materials functionalized with metal binding sites can be used to selectively remove soluble metal, but will not interfere with catalysis from immobilized metal. In this way the test can definitely distinguish between surface and solution catalysis of immobilized metal precatalysts.
This work investigates three different C-C coupling reactions catalyzed by the immobilized metal precatalysts mentioned above. These reactions include the Heck, Suzuki, and Kumada reactions. In all cases it is found that catalysis is solely from leached metal. Three different metal scavenging materials are presented as selective poisons that can be used to determine solution vs. surface catalysis. These selective poisons include poly(vinylpyridine), QuadrapureTM TU, and thiol-functionalized mesoporous silica. The results are contrasted against the current understanding of this field of research and subtleties of tests for distinguishing homogeneous from heterogeneous catalysis are presented and discussed.
Advisors/Committee Members: Dr. Christopher W. Jones (Committee Chair), Dr. E. Kent Barefield (Committee Member), Dr. Marcus Weck (Committee Member), Dr. Pradeep Agrawal (Committee Member), Dr. Rachel Chen (Committee Member).
Subjects/Keywords: Palladium catalysis; Cross coupling reaction; Heterogeneous vs. homogeneous; Selective poisoning; Palladium catalysts; Heterogeneous catalysis; Catalysis; Catalyst poisoning
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APA (6th Edition):
Richardson, J. M. (2008). Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/22704
Chicago Manual of Style (16th Edition):
Richardson, John Michael. “Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons.” 2008. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/22704.
MLA Handbook (7th Edition):
Richardson, John Michael. “Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons.” 2008. Web. 16 Jan 2021.
Vancouver:
Richardson JM. Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons. [Internet] [Doctoral dissertation]. Georgia Tech; 2008. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/22704.
Council of Science Editors:
Richardson JM. Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons. [Doctoral Dissertation]. Georgia Tech; 2008. Available from: http://hdl.handle.net/1853/22704
Georgia Tech
10.
Han, Man Huon.
Development of synthesis method for spinel ferrite magnetic nanoparticle and its superparamagnetic properties.
Degree: PhD, Chemistry and Biochemistry, 2008, Georgia Tech
URL: http://hdl.handle.net/1853/26465
► The magnetic spinel ferrite nanoparticle is exceptionally intriguing nanocrystal system due to the industrial importance of various technical applications and the scientific significance of studying…
(more)
▼ The magnetic spinel ferrite nanoparticle is exceptionally intriguing nanocrystal system due to the industrial importance of various technical applications and the scientific significance of studying the quantum origin of magnetism. Studies of quantum influences upon magnetic properties have revealed that the spin-orbit coupling and the net magnetization greatly affect the net magnetic properties of each spinel ferrite system differently. In case of cobalt ferrite where spin-orbit coupling is relatively large, increasing Cr3+ doping concentration, which has smaller magnetic moment and zero angular moment, decreases blocking temperature, saturation magnetization, remnant magnetization and coercivity. However, in case of manganese ferrite where spin-orbit coupling is relatively small, increasing Cr3+ doping concentration, reduces all the magnetic parameters except coercivity. The coercivity increases due to smaller magnetocrystalline anisotropy energy constant which forces the coercivity to increase as saturation magnetization decreases in accordance with Stoner-Wohlfarth theory. In order to improve product quality and quantity, synthesis routes in hot oleylamine and aminolytic reaction were developed. Both methods were proven to be extremely effective, environmental friendly, inexpensive, and simple routes in the synthesis of a variety of spinel ferrite systems including CoFe2O4, MnFe2O4, NiFe2O4, and ZnFe2O4 from a single source metal precursor.
Advisors/Committee Members: Z. John Zhang (Committee Chair), Angus Wilkinson (Committee Member), C P Wong (Committee Member), E. Kent Barefield (Committee Member), Mostafa El-Sayed (Committee Member).
Subjects/Keywords: Nanotechnology; Magnetism; Nanoparticle; Ferrites (Magnetic materials); Nanoparticles Magnetic properties; Spinel
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APA (6th Edition):
Han, M. H. (2008). Development of synthesis method for spinel ferrite magnetic nanoparticle and its superparamagnetic properties. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/26465
Chicago Manual of Style (16th Edition):
Han, Man Huon. “Development of synthesis method for spinel ferrite magnetic nanoparticle and its superparamagnetic properties.” 2008. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/26465.
MLA Handbook (7th Edition):
Han, Man Huon. “Development of synthesis method for spinel ferrite magnetic nanoparticle and its superparamagnetic properties.” 2008. Web. 16 Jan 2021.
Vancouver:
Han MH. Development of synthesis method for spinel ferrite magnetic nanoparticle and its superparamagnetic properties. [Internet] [Doctoral dissertation]. Georgia Tech; 2008. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/26465.
Council of Science Editors:
Han MH. Development of synthesis method for spinel ferrite magnetic nanoparticle and its superparamagnetic properties. [Doctoral Dissertation]. Georgia Tech; 2008. Available from: http://hdl.handle.net/1853/26465
Georgia Tech
11.
Sommer, William J.
Supported catalysts, from polymers to gold nanoparticles supports.
Degree: PhD, Chemistry and Biochemistry, 2007, Georgia Tech
URL: http://hdl.handle.net/1853/16140
► In today s world, the need to limit the use of nonrenewable resources and the importance of recycling has been recognized. One important contribution of…
(more)
▼ In today s world, the need to limit the use of nonrenewable resources and the importance of recycling has been recognized. One important contribution of chemists toward the general goal of limiting their use is to find catalysts that can be reused and recycled thereby limiting the need for expensive metal precursors and metal waste. Strategies to recycle catalysts are multifold and range from the employment of soluble polymers as catalyst supports to the use of membrane-encapsulated catalyst. The use of soluble polymers as a support not only offers the advantage of being soluble under the catalytic reaction conditions but also, to be removable by changing the conditions of the surrounding media. Despite the great potential of these soluble supported catalysts, their use is very limited in today s synthesis. In addition, no set of rules have been established to guide the synthesis of efficient supported catalysts. In order to establish a tool box for the synthesis of supported catalysts, the study of several parameters such as the choice of the support and the choice and the stability of the catalyst are necessary. To establish this set of rules, a limited number of catalytic transformations, were studied. These catalytic reactions are the Heck-Mizoroki, Suzuki-Miyaura and Sonogashira coupling reactions. These transformations became fundamental for the synthesis of drugs and materials. The first and second chapters provide background information by describing and evaluating the main supports that were previously used for catalysts and the two main catalysts that are used in this thesis, the palladium pincer complex and the palladium N-heterocyclic complex. In chapter 3, the synthesis of a soluble polymer supported catalyst is described. The polymer chosen for the study is poly(norbornene), and the catalyst is a 1,3-disubstituted benzene ligand with sulfurs in the side-chains able to chelate to the metal center, better known as pincer ligand. These ligands are abbreviated by the three atoms that coordinate to the metal center, in this study, SCS. The metal used for the investigation of the activity of this supported pincer is palladium. The importance of the nature of the linkage on the stability of the Pd-SCS pincer complex has been reported in the literature, leading to the synthesis of Pd-SCS pincer complex tethered to the polymer via an ether and an amide linkage. The synthesized poly(norbornene) supported Pd-SCS pincer complexes were evaluated using the Heck transformation of iodobenzene with n-butyl acrylate. Kinetic studies and leaching tests using poly(vinyl pyridine) and mercury were carried out resulting in the conclusion that the active species during the catalysis is not the palladium pincer complex but a leached palladium (0) species. In chapter 4, Pd-PCP pincer complexes with the ether and amide tether were synthesized. Kinetic and poisoning studies were carried out resulting in a similar conclusion. Furthermore, 31P NMR experiments were conducted to investigate the unstability of the complex.…
Advisors/Committee Members: Marcus Weck (Committee Chair), Christoph J. Fahrni (Committee Member), Christopher W. Jones (Committee Member), E. Kent Barefield (Committee Member), Mostapha A. El-Sayed (Committee Member).
Subjects/Keywords: Kinetic study; Heck reaction; Coupling chemistry; Poisoning; Suzuki reaction; Catalysts; Supported catalysts; Polymers; Gold nanoparticles; Polymers Synthesis; Water-soluble polymers; Catalysts Recycling
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APA (6th Edition):
Sommer, W. J. (2007). Supported catalysts, from polymers to gold nanoparticles supports. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/16140
Chicago Manual of Style (16th Edition):
Sommer, William J. “Supported catalysts, from polymers to gold nanoparticles supports.” 2007. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/16140.
MLA Handbook (7th Edition):
Sommer, William J. “Supported catalysts, from polymers to gold nanoparticles supports.” 2007. Web. 16 Jan 2021.
Vancouver:
Sommer WJ. Supported catalysts, from polymers to gold nanoparticles supports. [Internet] [Doctoral dissertation]. Georgia Tech; 2007. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/16140.
Council of Science Editors:
Sommer WJ. Supported catalysts, from polymers to gold nanoparticles supports. [Doctoral Dissertation]. Georgia Tech; 2007. Available from: http://hdl.handle.net/1853/16140
Georgia Tech
12.
Carlise, Joseph Raymond.
Poly(norbornene) supported side-chain coordination complexes: an efficient route to functionalized polymers.
Degree: PhD, Chemistry and Biochemistry, 2006, Georgia Tech
URL: http://hdl.handle.net/1853/10571
► This thesis begins with a brief overview of current strategies used in the synthesis of side-chain functionalizad polymers and materials. The discussion then focuses more…
(more)
▼ This thesis begins with a brief overview of current strategies used in the synthesis of side-chain functionalizad polymers and materials. The discussion then focuses more explicitly on transition metal-based motifs and methodologies that are employed in polymer functionalization and continues with a more detailed overview of this field.
The primary hypothesis that is addressed herein is that combining the versatility and strength of metal-ligand interactions with the efficiency and functional group tolerance of ROMP comprises a useful method of generating a variety of functionalized polymers and materials via side-chain metal coordination. Thus, the goal is to test this hypothesis by synthesizing functionalized polymers with a range of useful properties to demonstrate the relevance and importance of this methodology, by employing several different strategies to show the synthetic ease by which the materials can be realized.
The strategies and methods discussed in the synthesis of side-chain functionalized polymers are divided into three subgroups: (1) pre-polymerization functionalization, in which all of the modifications take place on the monomer with polymerization as the last step, (2) post-polymerization functionalization, in which the polymer itself is subsequently modified, and (3) combinations of the first two strategies.
It is shown that useful functional polymers and materials can be synthesized by any of the above strategies, and representative examples of each are given in both the introduction and in the body of work presented.
Modes of functionalization are all based on transition metal coordination, and polymerizations are primarily carried out via ROMP. Metal coordination is shown to be a useful technique for functionalizing polymers, to creating supported emissive complexes, to modulating solution viscosity.
Finally, conclusions are drawn regarding the various strategies presented herein, and potential future directions are discussed.
Advisors/Committee Members: Prof. Marcus Weck (Committee Chair), Prof. Charles Liotta (Committee Member), Prof. David Collard (Committee Member), Prof. Kent Barefield (Committee Member), Prof. Will Rees (Committee Member).
Subjects/Keywords: ATRP; Bipyridine; Chelation; Copolymers; Functional materials; Graft; Guar; Hydrolysis; Iridium; Ligands; Luminescent polymers; OLED; Photoluminescence; Photoluminescent; Polymerization; Polymers synthesis; ROMP; Ruthenium; Transition metal; Transition metal complexes; Viscosity
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APA (6th Edition):
Carlise, J. R. (2006). Poly(norbornene) supported side-chain coordination complexes: an efficient route to functionalized polymers. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/10571
Chicago Manual of Style (16th Edition):
Carlise, Joseph Raymond. “Poly(norbornene) supported side-chain coordination complexes: an efficient route to functionalized polymers.” 2006. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/10571.
MLA Handbook (7th Edition):
Carlise, Joseph Raymond. “Poly(norbornene) supported side-chain coordination complexes: an efficient route to functionalized polymers.” 2006. Web. 16 Jan 2021.
Vancouver:
Carlise JR. Poly(norbornene) supported side-chain coordination complexes: an efficient route to functionalized polymers. [Internet] [Doctoral dissertation]. Georgia Tech; 2006. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/10571.
Council of Science Editors:
Carlise JR. Poly(norbornene) supported side-chain coordination complexes: an efficient route to functionalized polymers. [Doctoral Dissertation]. Georgia Tech; 2006. Available from: http://hdl.handle.net/1853/10571
Georgia Tech
13.
White, Kathleen Madara.
Low Temperature Synthesis and Characterization of Some Low Positive and Negative Thermal Expansion Materials.
Degree: PhD, Chemistry and Biochemistry, 2006, Georgia Tech
URL: http://hdl.handle.net/1853/11582
► LOW TEMPERATURE SYNTHESIS AND CHARACTERIZATION OF SOME LOW POSITIVE AND NEGATIVE THERMAL EXPANSION MATERIALS Kathleen Madara White 151 pages Directed by Dr. Angus P. Wilkinson…
(more)
▼ LOW TEMPERATURE SYNTHESIS AND CHARACTERIZATION OF SOME LOW POSITIVE AND NEGATIVE THERMAL EXPANSION MATERIALS
Kathleen Madara White
151 pages
Directed by Dr. Angus P. Wilkinson
Low temperature non-hydrolytic sol-gel synthesis was used to explore the possibility of lowering the crystallization temperatures of some known AIVMV2O7 compounds. Crystallization temperatures for ZrP2O7 and ZrP2O7 were unaffected by the use of non-hydrolytic sol-gel methods; however, successful synthesis of these compounds broadens the range of materials that can be produced using this method and suggests the possibility of synthesizing solid solutions (or composites) including ZrP2O7 or ZrV2O7.
This research presents for the first time the direct synthesis of ZrP2O7 from separate zirconium and phosphorus starting materials using mild autoclave methods.
Characterization of some AIVMV2O7 compounds, using lab and high resolution synchrotron powder XRD, led to the assignment of a new symmetry for CeP2O7 and to the suggestion that the reported structure for PbP2O7 was inadequate. Studies using in situ high temperature lab and synchrotron powder XRD for PbP2O7 and CeP2O7 provided the opportunity to report their thermal properties for the first time, and to compare their behavior to that of some other AIVMV2O7. High pressure diffraction measurements on CeP2O7 provided data for the estimation of bulk moduli and suggested two possible pressure-induced phase transitions.
A broad range of MIIIMVP4O14 compounds were prepared using low temperature hydrolytic sol-gel synthesis. Thermal studies revealed nearly linear trends in CTEs and lattice constants with respect to the sizes of MIIIMV cations. Some lower ionic radii compounds had CTEs comparable to that of ZrP2O7 at low temperature, suggesting a similar superstructure. Three compounds were found to exhibit temperature-induced phase transitions.
Advisors/Committee Members: Angus P. Wilkinson (Committee Chair), E. Kent Barefield (Committee Member), Jiri Janata (Committee Member), John Zhang (Committee Member), Meilin Liu (Committee Member).
Subjects/Keywords: Thermal expansion; Negative thermal expansion; Low temperature synthesis; Pyrophosphates; Cation substitution; Materials Thermal properties; Pyrophosphates; Expansion (Heat); Expansion of solids
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APA (6th Edition):
White, K. M. (2006). Low Temperature Synthesis and Characterization of Some Low Positive and Negative Thermal Expansion Materials. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/11582
Chicago Manual of Style (16th Edition):
White, Kathleen Madara. “Low Temperature Synthesis and Characterization of Some Low Positive and Negative Thermal Expansion Materials.” 2006. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/11582.
MLA Handbook (7th Edition):
White, Kathleen Madara. “Low Temperature Synthesis and Characterization of Some Low Positive and Negative Thermal Expansion Materials.” 2006. Web. 16 Jan 2021.
Vancouver:
White KM. Low Temperature Synthesis and Characterization of Some Low Positive and Negative Thermal Expansion Materials. [Internet] [Doctoral dissertation]. Georgia Tech; 2006. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/11582.
Council of Science Editors:
White KM. Low Temperature Synthesis and Characterization of Some Low Positive and Negative Thermal Expansion Materials. [Doctoral Dissertation]. Georgia Tech; 2006. Available from: http://hdl.handle.net/1853/11582
Georgia Tech
14.
Meyers, Amy.
The Design and Synthesis of Metal-Functionalized Poly(norbornenes) for Potential Use in Light-Emitting Diodes.
Degree: PhD, Chemistry and Biochemistry, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/6985
► The use of polymers in electro-optical devices, especially light-emitting diodes (OLEDs), has become very popular in recent years, due to their ease of processability. The…
(more)
▼ The use of polymers in electro-optical devices, especially light-emitting diodes (OLEDs), has become very popular in recent years, due to their ease of processability. The major drawback of using polymers in these systems is their time-consuming synthesis when trying to improve upon their physical properties. For example, each time a new color or better conducting properties are desired, a new monomer must be synthesized. To circumvent these problems, the system described in this work is designed to connect the well-known chromophore aluminum tris(8-hydroxyquinoline) (Alq3) to a norbornene monomer unit, followed by polymerization using ring-opening metathesis polymerization (ROMP), thus allowing for the processability of a polymer while maintaining the fluorescent properties of the metalloquinolate.
The benefit of this system is that the monomers can be easily altered in order to tune color emission or to enhance the polymer properties. Some of the alterations include changing the metal center from aluminum to zinc in order to improve electron injection, adding substituents to the 8-hydroxyquinoline ligand in order to tune the emission color, and copolymerizing the Alq3-monomer with other norbornene monomers containing either a hole- or an electron-transport material side-chain to improve conductivity. These alterations lead to improved device performance and, more importantly, to a new method of designing polymeric systems for use in electronic devices.
Advisors/Committee Members: Marcus Weck (Committee Chair), Charles Liotta (Committee Member), Christopher Jones (Committee Member), David Collard (Committee Member), E. Kent Barefield (Committee Member).
Subjects/Keywords: Metaloquinolates; Fluorescent polymers; Poly(norbornenes); Light emitting diodes; Organic thin films; Fluorescent polymers
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APA (6th Edition):
Meyers, A. (2004). The Design and Synthesis of Metal-Functionalized Poly(norbornenes) for Potential Use in Light-Emitting Diodes. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/6985
Chicago Manual of Style (16th Edition):
Meyers, Amy. “The Design and Synthesis of Metal-Functionalized Poly(norbornenes) for Potential Use in Light-Emitting Diodes.” 2004. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/6985.
MLA Handbook (7th Edition):
Meyers, Amy. “The Design and Synthesis of Metal-Functionalized Poly(norbornenes) for Potential Use in Light-Emitting Diodes.” 2004. Web. 16 Jan 2021.
Vancouver:
Meyers A. The Design and Synthesis of Metal-Functionalized Poly(norbornenes) for Potential Use in Light-Emitting Diodes. [Internet] [Doctoral dissertation]. Georgia Tech; 2004. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/6985.
Council of Science Editors:
Meyers A. The Design and Synthesis of Metal-Functionalized Poly(norbornenes) for Potential Use in Light-Emitting Diodes. [Doctoral Dissertation]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/6985
Georgia Tech
15.
Barber, Jabulani Randall Timothy.
Mechanical compression of coiled carbon nanotubes.
Degree: PhD, Chemistry and Biochemistry, 2009, Georgia Tech
URL: http://hdl.handle.net/1853/28216
► Carbon nanotubes are molecular-scale tubes of graphitic carbon that possess many unique properties. They have high tensile strength and elastic modulus, are thermally and electrically…
(more)
▼ Carbon nanotubes are molecular-scale tubes of graphitic carbon that possess many unique properties. They have high tensile strength and elastic modulus, are thermally and electrically conductive, and can be structurally modified using well established carbon chemistries. There is global interest in taking advantage of their unique combination of properties and using these interesting materials as components in nanoscale devices and composite materials.
The goal of this research was the correlation of the mechanical properties of coiled carbon nanotubes with their chemical structure. Individual nanocoils, grown by chemical vapor deposition, were attached to scanning probe tip using the arc discharge method. Using a scanning probe microscope the nanocoils are repeatedly brought into and out of contact with a chemically-modified substrate. Precise control over the length (or area) of contact with the substrate is achievable through simultaneous monitoring the cantilever deflection resonance, and correlating these with scanner movement. The mechanical response of nanocoils depended upon the extent of their compression. Nonlinear response of the nanocoil was observed consistent with compression, buckling, and slip-stick motion of the nanocoil. The chemical structure of the nanocoil and its orientation on the tip was determined using scanning and transmission electron microscopy.
The mechanical stiffness of eighteen different nanocoils was determined in three ways. In the first, the spring constant of each nanocoil was computed from the slope of the linear response region of the force-distance curve. The assumptions upon which this calculation is based are: 1) under compression, the cantilever-nanocoil system can be modeled as two-springs in series, and 2) the nanocoil behaves as an ideal spring as the load from the cantilever is applied. Nanocoil spring constants determined in this fashion ranged from 6.5x10-3 to 5.16 TPa for the CCNTs understudy. In the second, the spring constant of the nanocoil was computed from measuring the critical force required to buckle the nanocoil. The critical force method measured the force at the point where the nanocoil-cantilever system diverges from a linear region in the force curve. Nanocoil spring constants determined in this fashion ranged from 1.3x10-5 to 10.4 TPa for the CCNTs understudy. In the third, the spring constant of each nanocoil was computed from the thermal resonance of the cantilever-nanocoil system. Prior to contact of the nanocoil with the substrate, the effective spring constant of the system is essentially that of the cantilever. At the point of contact and prior to buckling or slip-stick motion, the effective spring constant of the system is modeled as two springs in parallel. Nanocoil spring constants determined in this fashion ranged from 2.7x10-3 to 0.03 TPa for the CCNTs understudy.
Using the thermal resonance of the cantilever system a trend was observed relating nanocoil structure to the calculated modulus. Hollow, tube-like…
Advisors/Committee Members: Lawrence Bottomley (Committee Chair), Aldo Ferri (Committee Member), E. Kent Barefield (Committee Member), Levent Degertekin (Committee Member), Robert Whetten (Committee Member), Satish Kumar (Committee Member), Zhong Lin Wang (Committee Member).
Subjects/Keywords: Slip-stick; Tribology; Thermal resonance spectrum; Mechanical properties; Force spectroscopy; Atomic force microscopy; Nanocoil; Multi-walled carbon nanotube; Nanospring; Nanotube; Nanotubes Mechanical properties; Carbon; Chemical structure; Springs (Mechanism)
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APA (6th Edition):
Barber, J. R. T. (2009). Mechanical compression of coiled carbon nanotubes. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/28216
Chicago Manual of Style (16th Edition):
Barber, Jabulani Randall Timothy. “Mechanical compression of coiled carbon nanotubes.” 2009. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/28216.
MLA Handbook (7th Edition):
Barber, Jabulani Randall Timothy. “Mechanical compression of coiled carbon nanotubes.” 2009. Web. 16 Jan 2021.
Vancouver:
Barber JRT. Mechanical compression of coiled carbon nanotubes. [Internet] [Doctoral dissertation]. Georgia Tech; 2009. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/28216.
Council of Science Editors:
Barber JRT. Mechanical compression of coiled carbon nanotubes. [Doctoral Dissertation]. Georgia Tech; 2009. Available from: http://hdl.handle.net/1853/28216
Georgia Tech
16.
Carson, Cantwell G.
Noble and transition metal aromatic frameworks: synthesis, properties, and stability.
Degree: PhD, Materials Science and Engineering, 2009, Georgia Tech
URL: http://hdl.handle.net/1853/29657
► In the first section, the electrical conductivity of rhodium phenylene-diisocyanide polymer is reported to be 3.4E-11 S/cm. However, the conductivity also exhibits an inverse exponential…
(more)
▼ In the first section, the electrical conductivity of rhodium phenylene-diisocyanide polymer is reported to be 3.4E-11 S/cm. However, the conductivity also exhibits an inverse exponential decay in air with t = 8 days. This change is attributed to the oxidation of the isocyanide functional group to an isocyanate, leading to degradation in the long-range metal-metal bonding, the dominant conductivity mechanism. Using a more stable carboxylate ligand, the Cu terephthalate (TPA) system is studied and compared against the Mg, Co, Ni, and Zn terephthalates. A synthesis in N,N-dimethylformamide (DMF) is developed and large quantities of the Cu(TPA)DMF can be synthesized in air. The crystal structure of the Cu(TPA) DMF is shown to be in the C2/m spacegroup. Upon desolvation, the Cu(TPA) is shown to have a large surface area of 625 m2/g. The magnetic susceptibility of the Cu(TPA) indicates anti-ferromagnetic coupling between adjacent Cu centers in the same dimer. The thermal stability of the Zn, Ni, Co, and Mg terephthalates is shown to increase with decreasing symmetric carboxylate stretch in the IR. The magnetic susceptibilities of the Co and Ni terephthalates have paramagnetic behavior, with a Weiss temperature of T = -12.9 K and T = 8.8 for Co(TPA) DMF and Ni(TPA)DMF respectively. A heterometallic Zn-Cu terephthalate is synthesized with Cu concentrations ranging from 0 to 100%. Upon the addition of Cu, Zn-rich frameworks increase in surface area, change in thermal stability, and increase their solvent retention from 16% to 25%. Zn is shown to couple with Cu in the same dimer at a high rate, changing the behavior of the dimer from anti-ferromagnetic to paramagnetic. The Weiss temperature suggests weak ferromagnetic interaction.
Advisors/Committee Members: Rina Tannenbaum (Committee Chair), Rosario A. Gerhardt (Committee Co-Chair), E. Kent Barefield (Committee Member), Karl I. Jacob (Committee Member), Preet Singh (Committee Member), R. Bruce King (Committee Member).
Subjects/Keywords: Metal organic frameworks; Microporous; Coordination chemistry; MOF; Copper terephthalate; Organometallic chemistry; Organorhodium compounds; Aromatic compounds; Precious metals; Transition metal compounds
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APA (6th Edition):
Carson, C. G. (2009). Noble and transition metal aromatic frameworks: synthesis, properties, and stability. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/29657
Chicago Manual of Style (16th Edition):
Carson, Cantwell G. “Noble and transition metal aromatic frameworks: synthesis, properties, and stability.” 2009. Doctoral Dissertation, Georgia Tech. Accessed January 16, 2021.
http://hdl.handle.net/1853/29657.
MLA Handbook (7th Edition):
Carson, Cantwell G. “Noble and transition metal aromatic frameworks: synthesis, properties, and stability.” 2009. Web. 16 Jan 2021.
Vancouver:
Carson CG. Noble and transition metal aromatic frameworks: synthesis, properties, and stability. [Internet] [Doctoral dissertation]. Georgia Tech; 2009. [cited 2021 Jan 16].
Available from: http://hdl.handle.net/1853/29657.
Council of Science Editors:
Carson CG. Noble and transition metal aromatic frameworks: synthesis, properties, and stability. [Doctoral Dissertation]. Georgia Tech; 2009. Available from: http://hdl.handle.net/1853/29657
. 
Open Access Theses and Dissertations
