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The structure of the title compound consists of layers of metal centers linked through CH3PO3(super 2-) and C2O4(super 2-) ligands with charge compensating propylenediammonium cations and water molecules between the layers. Most oxalatophosphates have the oxalate unit acting as the bridge between metal phosphate layers.

The pure gamma isomer of the Keggin ion is crystallized as a tetrabutylammonium salt in a mixed H2O/CH(sub 3)CN solvent and is fully structurally characterized by single-crystal X-ray diffraction. The electronic behavior of the 2-electron-reduced oxo and oxothio derivatives are discussed and are related to the nature of the ligand E (O or S) and the metal (W or Mo).

The heteropolyanions (Bi2W22O74(OH)2)12- and (X2W20M2O70(H2O)6)(14-2n)- (X = Sb3+, Bi3+; M(super n+) = Fe3+, Co2+, Zn2+) were synthesized as alkali metal and ammonium salts, respectively. They were characterized by elemental analysis, infrared spectroscopy and X-ray crystallography. These tungsto bismutates and antimonates have one common characteristic: the trivacant beta-B-XW9O33 Keggin fragment as the structural building unit.

Single-crystal x-ray methods were used to identify the crystal structures of several novel alkylammonium phosphates. Findings indicated that the phosphates are arranged by layers and are separated by interdigitated or bilayers of organic amines. It was also observed that the cyclopentylammonium monohydrogen phosphate forms spontaneously in non-aqueous tetraethylene glycol starting synthesis mixture. Moreover, large crystals were also formed by recrystallization of the phosphates.

Alkylammonium cations are directly involved in the formation and subsequent stabilization of cagelike polysilicate anions, indicating a different mechanistic role than 'templating' for these cations in the synthesis of molecular sieves. This was gleaned from an examination of the kinetics of formation of the silicate cubic octamer Q(super 3)(sub 8) in aqueous tetramethylammonium silicate solutions, using 29Si nuclear magnetic resonance spectroscopy.

A systematic study of tetraalkylammonium silicate equilibria using nuclear magnetic resonance spectroscopy has found that protective shells of solvated organocations surround individual cage-like polyanions, hindering hydrolysis of the central anion. Tetraalkylammonium cations added to aqueous silicate solutions enhances the abundance the symmetric, cage-like, polysilicate anions. For solutions with a concentration ratio (OH-):(Si) >/- 1:1, the equilibrium ratio of tetramethylammonium cations to the octameric silicate anion is 8:1.

The compound NH4Fe2(PO4)2 is the first ammonium mixed-valence iron phosphate and the first ammonium transition-metal phosphate to be synthesized by high-temperature, high-pressure hydrothermal synthesis. Its original structure has chains of edge-sharing Fe(II)O6 octahedra and chains of corner-sharing Fe(III)O6 octahedra and PO4 tetrahedra. Mossbauer spectroscopy indicated the presence of equal amounts of Fe(II) and Fe(III).

The phase change in phases II and II of N(CH3)4IO4 is a result of the commencement of free ion rotation rather than the rotational oscillation axes' positional disorder, according to research of its Raman spectra and crystal structures. The finding is in agreement with L. Pauling's initial proposal. In high temperature phase I, both ions are believed to be rotationally disordered; in room-temperature phase II, the lesser counterion is rotationally disordered while the greater ion is ordered; in low-temperature phase III, the cation and anion are both ordered.

The solvent variation of (bpy)2Ru(Cl)(pyz)(NH3)5L4+; where bpy is 2,2-bipyridine, pyz is pyrazine, and L is ammonia or pyridine; results in specific hydrogen-bonding interaction of the donor solvent with coordinated ammonia (NH3). The data fits of redox potentials and intervalence electron transfer energy yields the potential energy surfaces of ground and excited states. The bases undergo electrostatic interactions with coordinated NH3. The non-specific solvation has a major contribution in the Franck-Condon barrier.

The ammonium nickel molybdate, (NH4)HNi2(OH)2(MoO4)2, synthesized by precipitation from a solution of nickel nitrate and ammonium heptamolybdate has a trigonal structure with hexagonal unit cell parameters. Synchrotron radiation was used to get an X-ray diffraction pattern of the compound. The structure was determined using Patterson and difference Fourier density maps and refined using the Rietveld technique. Molybdate tetrahedra and nickel octahedra form layers perpendicular to the c axis of the compound with ammonium ions placed between the layers.

Single-crystal X-ray diffraction is used to examine solid solutions of a Jahn-Teller active compound in an undistorted host. The variations of unit cell parameters are monotonic at high Cr concentrations. The introduction of even a 0.07 mole fraction of Zn induces a shift in direction of the Jahn-Teller distortion at the chromium center.

Synthesis of new energetic salts (2, 3, 5, 6, 13, 14, 21, 22) was done via the quaternization of derivatives of N-aminoazoles with nitric or perchloric acid or with iodomethane followed by metathesis reaction with silver nitrate or silver perchlorate. Single-crystal X-ray analysis confirmed the structure of 2-amino-4,5-dimethyltetrazolium nitrate (21).

Low temperature single-crystal neutron structures (15K) and Raman spectra of the salts (NX4)(sub 2)[Cu-(OX2)(sub 6)](SO4)(sub 2), where X = H or D are described. The Raman spectra provide no intimation of any significant change in the intermolecular bonding. The small structural differences suggest different relative stabilities for the hydrogenous and deuterated salts.

Research has been conducted on the zeolite analogues. The stability and synthesis of these analogues have been investigated and the development of the synthetic route to the ABW-type ammonium zinc arsenate is described.

Reduced binary metal oxides of chromium, iron, tungsten and molybdenum were obtained by the addition of hydroxylamine hydrochloride in aqueous solutions of ammonium salts at a fixed pH and maintained by adding hydrochloric acid drops. This method was found to have the potential to lead to the formation of ternary oxides in the presence of other cations. The technique may be applicable to the synthesis of metastable or low temperature phases with interesting physical and structural properties.

Several alkylammonium and bipyridinium salts of hyponitrous acid and hyponitrite salts were synthesized by the reaction of the corresponding amine in either anhydrous diethyl ether or absolute ethanol with hyponitrous acid. Single-crystal X-ray crystallographic data were gathered. Differential scanning calorimetric data showed exothermic decomposition of the hyponitrite species. The pentahydrate and anhydrous forms of Na2N2O2 showed unique thermal decomposition behavior.