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THE HOT-ATOM CHEMISTRY OF MOLYBDENUM CARBONYL - TRIFLUOROPHOSPHINE COMPLEXESUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-06, Section: B, page: 2665. / Thesis (Ph.D.)--The Florida State University, 1979.
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BONDING STUDIES IN SOME TRANSITION METAL COMPLEXES: PART I, ORIGINS OF ELECTRIC FIELD GRADIENTS IN CESIUM TRICHLORO-NICKELATE(II), CESIUM TRICHLORO-CUPRATE(II), POTASSIUM TRICHLORO-CUPRATE(II); PART II, PARAMAGNETIC RESONANCE STUDY OF BONDING IN SOME PENTAMMINECHROMIUM(III) COMPLEXESUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-11, Section: B, page: 6280. / Thesis (Ph.D.)--The Florida State University, 1971.
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A STUDY OF SYNTHETIC APPROACHES TO DIFERROCENYL AND TRIFERROCENYL LIGANDSLIGANDSUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-12, Section: B, page: 6897. / Thesis (Ph.D.)--The Florida State University, 1971.
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SYNTHETIC AND SINGLE CRYSTAL NUCLEAR MAGNETIC RESONANCE STUDIES OF THE METAL CARBONYLSUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-11, Section: B, page: 6282. / Thesis (Ph.D.)--The Florida State University, 1971.
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VIBRATIONAL SPECTRA OF CARBON-13 CARBON-MONOXIDE-SUBSTITUTED POLYMETALLICCARBONYLSUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-11, Section: B, page: 6284. / Thesis (Ph.D.)--The Florida State University, 1971.
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MIXED TRIFLUOROPHOSPHINE - CARBONYL IRON COMPOUNDS AS PHOTOCATALYTIC PRECURSORS IN ISOMERIZATION STUDIESUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 38-09, Section: B, page: 4231. / Thesis (Ph.D.)--The Florida State University, 1977.
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Synthesis, characterization, and reactivity of group 6 metal (molybdenum and tungsten) complexes with porphyrin ligandsUnknown Date (has links)
The structures, physical properties, and reaction chemistry of molybdenum (V) and tungsten (V) porphyrin complexes are investigated. The four, five-coordinate nitrido molybdenum (V) and tungsten (V) complexes MoN(TMP), MoN(TPP), MoN(TTP), and WN(TPP) have been synthesized and characterized by mass, ESR, IR, and UV-Visible spectroscopic methods. Furthermore, one of the nitrido complexes MoN(TMP) and imido derivative (Mo(NMe)(TPP)(H$\sb2$O)) $\sp+$(I$\sb3$)$\sp-$ have been characterized by single-crystal X-ray diffraction techniques. MoN(TMP) has a square pyramidal structure in the solid state, with the Mo-nitrido bond length of 1.630 (4) A and nitrogen atom at the apical position. The terminal nitrido ligand is triply bonded to the metal. Nitrido complexes MoN(TMP) and MoN(TPP) form 1:1 adducts with Lewis acid, methylates at nitrogen atom upon reaction with methyl iodide, displaces one CO ligand from Mo(CO)$\sb6$, and react with HCl gas to produce (porph)MoN--BF$\sb3$, (Mo(NMe)(TPP)(H$\sb2$O)) $\sp+$(I$\sb3$)$\sp-$, (TPP)MoN--Mo(CO)$\sb5$, and ((porph)MoN--H) $\sp+$Cl$\sp-$, respectively. Also, nitrido complexes react with tertiary alkyl phosphines to form phosphineiminato complexes. (Mo(NMe)(TPP)(H$\sb2$O)) $\sp+$(I$\sb3$)$\sp-$ has a distorted octahedral structure in the solid state, with the Mo-imido bond length of 1.689 (6) A and the Mo-N-CH$\sb3$ angle of 175.34 (64)$\sp\circ$. Thus, the imido ligand in this compound acts as a four $\pi$-electron donor. / Quadruply bonded (W(TPP)) $\sb2$ and its reaction derivative WN(TPP) also have been synthesized. Diamagnetic tungsten dimer (W(TPP)) $\sb2$ shows the very similar spectroscopic patterns to those of (Mo(TPP)) $\sb2$. Temperature dependent $\sp1$H NMR spectra of this complex show two NMR distinct $\beta$-pyrrole protons at $-$48$\sp\circ$C due to the rotation about $\delta$ component tungsten-tungsten quadruple bond. The activation barrier was estimated 11.3 kcal/mole from the NMR line shape analysis. (W(TPP)) $\sb2$ reacts with p-tolyl azide to produce paramagnetic WN(TPP). / Source: Dissertation Abstracts International, Volume: 52-03, Section: B, page: 1425. / Major Professor: Virgil L. Goedken. / Thesis (Ph.D.)--The Florida State University, 1991.
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Non-Aqueous Transuranic Coordination ComplexesUnknown Date (has links)
As of 2014, there is an expected 69,000 metric tons of nuclear waste sitting in storage in the U.S. Little efforts have been made to
deal with the radiotoxicity of the spent nuclear fuel (SNF). The problem arises from the complex mixture of the SNF and highly radioactive
actinides. Due to the high radioactivity of the minor actinides (Pu-Cm), there is a lack of understanding the fundamental chemistry of the
actinides. The focus of this work is to prepare coordination complexes that can be used as probes for elucidating changes in the structure
and bonding across the actinides series Most coordination chemistry that has been studied with the actinide series has only utilized ligands
stable to oxygen and moisture due to the difficulties of handling the transuranium actinides. The chemistry of non-aqueous ranium has made
great progress, while, the non-aqueous chemistry of the transuranic elements is relatively unexplored and offers a wider platform for
exploring methods of deducing electronic structure and information about the actinide-ligand bond. Such information can be very useful for
discovering trends in the whole series. The beginning chapters focus on simple coordination compounds using soft N and S donor ligands for
complexing Am-Cf. Since very little structure data is known for these elements and softer donor ligands have shown to have a preference over
trivalent actinides than lanthanides, we focus on these systems to understand the trends in bonding across the 5f series. Chapter 4 focus on
a series (U-Cf) of complexes using the redox active ligand 2,4,6,8-tetrakis(tert-butyl)-9-hydroxyphenoxanone (HDOPO) were synthesized in
non-aqueous conditions under an inert atmosphere and have been fully characterized by X-ray, optical, magnetic, and computational techniques.
Spectroscopic data reveals the An(DOPO)3 complexes of the earlier actinides being the tetravalent state, in contrast to the later actinides,
they are in the trivalent state. Furthermore, the Cf(III) complex disrupts the tris-chelate trend due to radiolysis. It is also shown that
the ligand undergoes redox transitions to stabilize the higher oxidation states of the earlier actinides. The results will help contribute
toward gaining foundational knowledge of structure and bonding in non-aqueous transuranic chemistry as well as give insight into the
participation of f-orbitals in bonding. The ending chapters are out of the scope of non-aqueous chemistry but projects that pertain to the
nature of the actinide series. As the first focuses on the effects of radiolysis. As we go to the heavier actinides, radiolysis affects the
crystallization of our targeted products. In this case, an aged thorium source produces peroxide over time changing the result of the
product. Lastly, is an example of driven degeneracy covalency in an americium chromate system. It was thought the later actinides tend to be
more ionic, however we are finding small amount of covalent character partakes in the bonding. Collectively, this body of work primary focus
is elucidating the structure and bonding of the f-elements through coordination complexes utilizing various techniques. / A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the
requirements for the degree of Doctor of Philosophy. / Fall Semester 2017. / November 13, 2017. / Includes bibliographical references. / Vladimir Dobrosavljević, University Representative; Kenneth Hanson, Committee Member; Michael Shatruk,
Committee Member.
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Redox and Coordination Chemistry Differences of the 4f and 5f ElementsUnknown Date (has links)
This dissertation seeks to determine the differences in the lanthanides and later actinides in non-aqueous media. Research in the f-elements is significantly understudied compared to the other metals of the periodic table. Even more so are the later actinides which were largely unstudied for an extended period as it was believed later actinides were identical to lanthanides. A review by Neidig et al, “The Covalency in f-element Complexes” has ignited significant interest in the bonding of the actinides.1 A tremendous amount of research in the f-elements, particularly the actinides, has been performed in aqueous conditions at high temperatures and pressures. Chemistry under these conditions limit the research possible for lower oxidation states. Additionally, non-aqueous techniques allow for the investigation of these elements in more organic environments. The goal of this work is to pave a greater understanding of knowledge for lanthanides and actinides by examining their redox and coordination chemistries in these environments that could lead to applications other than nuclear energy and weapons. The first portion of this dissertation examines the chemistry that is already heavily acknowledged about f-elements: coordination chemistry. When modeling later actinides, a common notion is to utilize the isoelectronic lanthanide as the surrogate. Although for electronic comparisons this is useful, it is often not the case for examining isostructural compounds. The isoelectronic lanthanide is often smaller in ionic radius, which is a factor that dominates the chemistry of the lanthanides. Despite this, isolation of isostructural coordination compounds was obtained for the isoelectronic and size analogs of americium; europium and neodymium. This seemingly mundane study showed that americium portrays a small amount of covalency in its bonds which is not observed in the lanthanides. These small differences lead to profound changes in chemical properties as observed later in this work. The second portion of this work focuses on analyzing the divalent oxidation state of f-elements with crown ethers. The divalent oxidation state has been obtained for all lanthanides using potassium and 2.2.2-cryptand. The next step was to determine the extent to which crown ethers and solvents have on the redox properties of f-elements. Because all the lanthanides had been obtained in the divalent oxidation state in a similar matter, it was expected that the redox chemistries would behave identically. To surprise, ytterbium behaves differently and shows greater reversibility than the most stable divalent lanthanide, europium. Additionally, it was found that californium also behaves like ytterbium electrochemically, even though it would be expected to behave like samarium. It was proposed that this may be attributed to the 5f orbitals. The last of this work involves obtaining californium in the divalent oxidation state as a molecular system. This was done by modeling with samarium which is the most similar to californium in its redox and coordination properties. Quick and simple routes to synthesizing divalent samarium structures were obtained in ordinary glovebox conditions for attempts with californium. Under identical reaction conditions, isolation of Cf(II) crystals in the solid state were unsuccessful. However, interesting spectroscopic properties where observed that portrayed divalent californium as having tunable luminescence similar to divalent europium compounds. To our surprise, even though samarium resembles californium, the chemistry between the two elements are very different, further broadening the gap between the 4f and 5f elements. / A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2018. / September 28, 2018. / Actinides, Californium and Americium, Coordination Chemistry, Divalent Samarium, Lanthanides, Redox Chemistry / Includes bibliographical references. / Thomas E. Albrecht-Schmitt, Professor Directing Dissertation; Samuel L. Tabor, University Representative; Kenneth G. Hanson, Committee Member; Yan-Yan Hu, Committee Member.
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A THERMODYNAMIC STUDY OF THE ACTINIDE-MONOFLUORIDES AND THE EFFECTS OF CHANGES IN IONIC MEDIAUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 35-04, Section: B, page: 1559. / Thesis (Ph.D.)--The Florida State University, 1974.
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