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The synthesis and crystal structures of two transition metal-based (Zn, Ni) coordination polymers comprising ligand molecules formed during hydrothermal treatment is described. The process involves dimerization via C-N bond formation for zinc, and C-C bond formation for nickel.

The transition-metal-incorporated nickel phosphate molecular sieves (TMI-VSB-5) are hydrothermally synthesized at 453 K in weak basic conditions under microwave irradiation. The study demonstrated the nanoporous VSB-5 has a versatile framework to accommodate various TMIs with several oxidation states and symmetries.

High-pressure synchroton X-ray powder diffraction measurements of a sample of purely siliceous zeolite Y were carried out. Rietveld refinement analysis of the powder patterns provides a detailed description of the underlying chemistry and framework distortions at higher pressures.

Sorption, neutron scattering, and temperature desorption experiments points toward the existence of unsaturated Ni(super 2+) sites in VSB-5 that strongly interact with H2. The discovery of unique interactions with molecular hydrogen in these materials should motivate a search for new compounds in this family tailored for H2 uptake.

An alternative route to molybdenum disulfide nanotubes is proposed.

A new study investigates the characterization of the local cation environment and possible site preferences in mixed lithium-sodium chabazites, using solid-state NMR and neutron diffraction.

Issues concerning the use of Ramon spectroscopy and inelastic neutron scattering to observe the strength and nature of interactions between tricholorethylene sorbates, chloroform and siliceous FAU, NaY, and NaZ zeolites are presented.

A study was conducted to analyze the energetics and structures of fluoro- and chlorofluorocarbons in zeolites. The major features of fluorocarbon adsorption were rationalized based on the respective components of the total adsorption energies and the analysis of host-guest pair functions. Results indicated very good agreement between experiment and simulation for the selection of fluoro-, fluorochloro-, and hydrofluorocarbon/zeolite systems.

A study was conducted comparing Monte Carlo simulations and results of calorimetric measurements on the adsorption of chlorocarbons, chloroform and three faujasite type zeolites of trichloroethylene and siliceous faujasite. Quantitative agreement was found between the calculated and observed heats as a function of sorbate loading for all six systems. Decomposition of calculated heats showed that sorbate-sorbate interactions were important to the three zeolite hosts and led to an increase in the adsorption heat.

A study was conducted to analyze the structure and energetics of chloroform binding sites in NaY zeolite using vibrational spectroscopy and energy-minimization computations. The binding sites were also examined by the Monte Carlo packing procedure. A closed-cycle He refrigerator was utilized to obtain the inelastic neutron scattering spectrum. Experimental results indicated that the H atoms of chloroform molecules influence hydrogen bonding with the framework oxygens.

The structure of the silicate species was determined utilizing the Hartree-Fock technique and the 29Si NMR magnetic shielding constants were subsequently computed using the coupled perturbed Hartree-Fock technique with gauge including atomic orbitals. The silicate monomer was modeled as a neutral fully protonated species, H4SiO4 and as a monoanion-potassium cation pair, H(sub 3)SiO(sub 4)(super -)K(super +). Hydration by up to four and two water molecules, respectively, was also considered.

The role of structure-directing agents during the crystallization stage in the synthesis of two zeolites, siliceous ferrierite and dodecasil-3C, were investigated using x-ray spectroscopic methods. The two zeolites, which contain five-ring building blocks, may be prepared using hexagonal faujasite and pyridine as solvents. According to x-ray measurements, the first contains propylamine while the latter contains both propylamine and pyridine.

Synchrotron x-ray and neutron powder diffraction studies of the crystal structures of siliceous zeolite ferrierite reveal the presence of a Si-O-Si unit with a bond angle of 170 degrees. Crystal structures predicted by lattice energy minimization method agree with the experimental observations. A bond angle correlation helps assign the well-resolved 29Si magic angle spinning NMR spectrum. This assignment helps determine Si/Al ratios in the multiple T-site system and analyze the complex spectra of various aluminosilicate ferrierite samples.

Conformational, X-ray crystallographic and solution H NMR studies of the two cis-dihydrotritylbiphenyl isomers reveal that their individual substituent conformations are pseudoequatorial. Cis-isomer phenyl substituent orientation occurs along the dihydroaromatic ring's C(1)-C(4) axis. A comparison of the solid state geometries of cis- and trans-dihydrotritylbiphenyl isomers reveals that the cyclohexadiene boat is nearly planar for the isomer types. Both the cis-isomers adopt a close intramolecular edge-to-face aromatic conformation.

Erbium selenite(IV) selenate(VI) hydrate was synthesized hydrothermally and characterized by X-ray absorption near edge structure measurements. The compound consisted of isolated trigonal pyramidal selenite(IV) anions and tetrahedral selenate(VI) groups. The erbium atoms were eight-coordinated by oxygen. The structure had a pseudolayered type arrangement with the selenium(VI) atoms disordered over two sites.

The valence distribution of Fe2+ and Fe3+ in alpha-Fe2PO5 was investigated by the resonant X-ray and neutron powder diffraction using a Rietveld profile refinement program. The direct cation-cation interactions and cation-anion- cation interactions were studied based on the proposition that the two cations belong to two distinct crystallographic sites. The results were then compared with bond valence calculations.

The synthesis of new phases and crystal structures of 11 alkaline earth tartrates, including an unusual [I.sup.3][O.sup.0] framework [Ba(D,L-Tar)] (Tar = [C.sub.4][H.sub.4][O.sub.6.sup.2-]), with 3-D inorganic connectivity is described. The results have shown that the calcium and strontium meso phases are the most thermodynamically stable phases in their systems over a wide temperature range.

The application of nanoindentation and atomic force microscopy to establish the fundamental relationships between mechanical properties and chemical bonding in a dense inorganic-organic framework material, Ce([C.sub.2][O.sub.4])(HC[O.sub.2]) is reported. The study provides insight into vast opportunity to design the mechanical properties of dense hybrid framework materials through the incorporation of organic multifunctional ligands of varying rigidity.

Multiferroic behavior in perovskite-related metal-organic frameworks of general formula [[(C[H.sub.3]).sub.2]N[H.sub.2]M[(HCOO).sub.3], where M = Mn, Fe, Co, and Ni, is described. These compounds have displayed paraelectric-antiferroelectric phase transition behavior in the temperature range 160-185 K, which is associated with an order-disorder transition involving the hydrogen bonded dimethylammonium cations.

Tc[Br.sub.3] and Tc[Br.sub.4] are prepared by reaction between Tc metal and elemental bromine and characterized by using single crystal XRD. The Tc[Br.sub.3] has displayed the Ti[I.sub.3] structure type, the Tc[Br.sub.4] is isomorphous with Tc[Cl.sub.4] and the bromides of technetium are unique and do not match the behavior of Re.

The synthesis of four organic-inorganic frameworks of alkaline earth cations with the organic ligand 2,5-thiazolo[5,4-d]thiazoledicarboxylate is described. The resulting frameworks have shown how increasing the cation size and coordination requirements have led to greater inorganic connectivity in this system.

An order-disorder type electrical ordering is described at 156 K in [[(C[H.sub.3]).sub.2]N[H.sub.2]]Zn[(HCOO).sub.3]. A hybrid system with the perovskite architecture is described that has displayed a ferroic transition between paraelectric and antiferroelectric states.

The modification of the hydrolysis reaction into a protolysis reaction by using inorganic acids instead of water is examined. The studies have shown that with every ammonium halide used as a protolysis agent, [C.sub.3][H.sub.4] and the respective magnesium halide are obtained as the byproducts, which can be converted to magnesium metal by electrolytic routes.

The complete structure of Tc[O.sub.2] obtained from Rietveld refinement with neutron powder diffraction data is presented.

The synthesis and structure of three compounds based on the M(II)/1,2-ethylenediphosphonic acid system and one based the M(II)/1, 10-phenanthroline/1,2-ethylenediphosphonic acid system (where M = Co, Ni, Mn) are described. The asymmetric unit the complex shows that the [M.sup.2.plus] is six-coordinate with a distorted [M.sup.II][O.sup.5]([H.sub.2]O] octahedron and the phosphonate group (bonded to the [M.sup.2+) is fully deprotonated and that all of the oxygens o the phosphonate group are involved in [M.sup.2+] -O bonds.

Study is conducted to show that a porous hybrid inorganic/organic material, Na[Ni.sub.3](OH)[(SIP).sub.2] [SIP=5-sulfoisophthalate] (1) strongly binds molecular hydrogen at coordinatively unsaturated metal sites. A combination of [H.sub.2] sorption isotherms, temperature programmed desorption, and inelastic neutron scattering spectroscopy show the existence of a significant number of such strong binding sites in (1) along with other sites where hydrogen is more weakly physisorbed.

A three-dimensional iron(III) diphosphonate, Fe(super III)(H2O)(HO3P(CH2)2PO3) is synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The structure consists of inorganic sheets pillared by the 1,2-ethylenediphosphonate groups.