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In the past decade, the field of NMR spectroscopy has seen the emergence of ever more powerful superconducting magnets, which has opened the door for the observation of many traditionally challenging or non-receptive nuclei. In this dissertation, a variety of ionic solids with organic coordination environments are investigated using quadrupolar solid-state NMR experiments with an ultrahigh-field magnet (21.1 T). Two general research directions are presented including a 79/81Br solid-state NMR study of a series of 6 triphenylphosphonium bromides for which single-crystal X-ray structures are reported herein. A second research direction is also presented wherein alkaline-earth metal (25Mg, 43Ca, and 87Sr) solid-state NMR is used to characterize a systematic series of 16 aryl and alkyl carboxylates. In both studies, the quadrupolar nuclei studied are deemed “exotic” due to their unreceptive nature to NMR spectroscopic analysis including low natural abundances, large quadrupole moments, or low resonance frequencies. A variety of coordination modes to alkaline-earth metals, including N-atom coordination, are characterized herein for the first time using alkaline-earth metal solid-state NMR. In all cases, the electric field gradient (EFG) and chemical shift (CS) tensors are characterized and correlated to structural features such as interatomic distances measured from the crystal structure of the compound under study. In all of the projects undertaken herein, the gauge-including projector-augmented-wave density functional theory (GIPAW DFT) method is used, which allows for the prediction and rationalization of the experimental EFG and CS tensor parameters based on the input crystal structure. In the case of 43Ca solid-state NMR experiments reported in this dissertation, a linear correlation between the calculated and experimental 43Ca quadrupolar coupling constants, CQ, is used as a calibration curve for GIPAW DFT calculations performed on the 18 structural models currently available for the vaterite polymorph of CaCO3. Vaterite cannot be fully characterized by X-ray diffraction alone; therefore an NMR crystallography protocol is used in order to identify the model that best accounts for 43Ca solid-state NMR experiments performed on vaterite. It is expected that the conclusions from this dissertation can be used for future studies involving structural refinement and elucidation of solid materials containing challenging quadrupolar nuclei.

La chimie des métaux alcalino-terreux lourds (calcium, strontium et baryum) a longtemps été décrite comme difficile et imprévisible contrairement à la chimie du magnésium, leur plus léger congénère. Cependant, au cours des dernières décennies, de nombreux complexes basés sur ce type de métaux ont émergés en tant que précatalyseurs efficaces pour un grand nombre de transformations organiques (polymérisation, hydroélémentation, couplage déshydrogénants, etc..). Cette thèse décrit la synthèse et l’étude (expérimentale et théorique) de nouveaux complexes de baryum de basse coordinance basée sur l’utilisation de ligands alcoolates pauvres en électrons. L’étude de ces composés a permis d’améliorer notre compréhension des différents phénomènes nécessaires à la stabilisation de tels composés. Dans un second temps, deux nouveaux systèmes de couplages déshydrogénants BO‒H/H‒Si et SiO‒H/H‒Si ont été développés et étudiés. Ces systèmes ont permis la formation catalytique de borasiloxanes et de siloxanes dissymétriques de façon sélective. Enfin, ces travaux montrent la synthèse et l’utilisation de nouveaux ligands ancillaires pour la formation de complexes hétéroleptiques de baryum stables. Ces derniers ont démontré une forte activité catalytique en hydrophosphination intermoléculaire avec des TOF pouvant atteindre 200 h-1 pour l’hydrophosphination du styrène par la HPPh2. / Heavy alkaline earth metals chemistry (calcium, strontium and barium) has been described as difficult and unpredictable for a long time, unlike the chemistry of magnesium, their lightest congener. However, in the last decades, many complexes based heavy alkaline earth metals have emerged as effective precatalysts for many applications and organic transformations (polymerization, hydroelementation, dehydrogenating coupling, etc.). This thesis describes the synthesis and study (experimental and theoretical) of new low-coordinate barium complexes based on electron-poor alkoxide ligands. The study of these compounds has improved our understanding of the different phenomena required to stabilize such compounds. Then, two new dehydrocoupling systems BO-H/H-Si and SiO-H/H-Si were developed and studied. These systems have allowed the catalytic formation of borasiloxanes and asymmetric siloxanes in a selective manner. Finally, this work shows the synthesis and use of new ancillary ligands for the formation of stable heteroleptic barium complexes. The latter have demonstrated strong catalytic activity in hydrophosphination with TOFs up to 200 h-1 for the intermolecular hydrophosphination of styrene by HPPh2.

No description available.

We may summarize the purposes of this investigation as follows: A report on this investigation was made to Dr. John H. Yoe of the University of Virginia in order to see what reactions he considered to be of analytical significance and should be further investigated. He considers only three to be of any practical importance. They are as follows: 1. 7A-Oleic Acid. Solubility of the alkaline earth salts of some higher fatty acids. 2. 69A- 2-Acetamino 6-Aminobenzo Thiazole. A colorimetric reagent for iridium. 3. 71A 2-Hydroxy 3-Nitro 5-Sulfobenzoic Acid. A colorimetric reagent for ferric iron. A further investigation of compound 71A, as a colorimetric reagent for ferric iron, reveals that the sensitivity of this reaction is not great enough for it to be of any practical importance, since we have reagents (2) for this ion that are several times more sensitive. Prospective reagent No. 69A for iridium is being further investigated by Mr. J. R. Noell (1). A report on 7A will be taken up in Part II of this thesis. 1. It has been shown that there is very little difference in the solubility of the same alkaline earth salt of stearic, oleic, linoleic, and linolenic acids in the solvents, water, benzene, absolute ethyl alcohol and ether. 2. It has been shown that there is very little difference in the solubility of the different alkaline earth salt of stearic, oleic, linoleic, and linolenic acids in the solvents, water, benzene, absolute ethyl alcohol and ether, and benzene. 3. The solubility of the alkaline earth salt of these acids increases slightly with unsaturation, but does not increase as the degree of unsaturation increases. / M.S.

Nine beryllium deposits were studied in order to determine the geological environment of beryllium mineralization in southern Arizona. Beryllium occurs in two pegmatite areas, two contact metamorphic deposits, two quartz-tungsten veins, two quartz-feldspar veins, and in one quartz monzonite stock. It is associated in almost all of these deposits with purple fluorite and tungsten. Beryllium mineralization is associated with granitic and quartz monzonite intrusions of Laramide age, and generally occurs at the intersection of northwest-trending lineaments and the Texas lineament.

No description available.

A large amount of information concerning interatomic distances in the solid state is available, but little has been done in recent times to comprehensively filter, summarize and analyze this information. Here, I examine the distribution of bond lengths for 135 ions bonded to oxygen, using 180,331 bond lengths extracted from 9367 refined crystal structures collected from the Inorganic Crystal Structure Database (ICSD). The data are used to evaluate the parameterization of the bond-length—bond-valence relation of the bond-valence model. Published bond-valence parameters for 135 cations bonded to oxygen, and the various methods used in their derivation, are evaluated. New equations to model the relation are tested and the common form of the equation is found to be satisfactory. A new method (the Generalized Reduced Gradient Method, GRG method) is used to derive new bond-valence parameters for 135 cations bonded to oxygen, leading to significant improvements in fit for many of the ions. The improved parameterization is used to gain crystal-chemical insight into the milarite structure. A literature review of 350+ published compositions is done to review the end-members of the milarite group and to identify compositions that should have been described as distinct minerals species. The a priori bond-valences are calculated for minerals of this structure, and are used to examine the controls of bond topology on site occupancy, notably by localizing the major source of strain of the structure (the B site). Examination of the compositions of all known milarite-group minerals shows that compositions with a fully occupied B site are less common than those with a vacant B site, in accord with the idea that the B site is a local region of high strain in the structure. The bond-length distributions for the ions of the alkali and alkaline-earth metal families are examined. Variations in mean bond-lengths are only partly explained by the distortion theorem of the bond-valence model. I have found that bond length also correlates with the amount of vibrational displacement of the constituent ions. The validity of some uncommon coordination numbers, e.g., [3]-coordinated Li+, [3]-coordinated Be2+, is confirmed. / October 2016