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The mass spectrometric identification of dimeric species in the SnBr2-SnI2 system is presented. The discussion on the implications of the thermodynamic and structural data obtained by theoretical methods on the observed fragmentation paths of the neutral Sn2BrxI(sub 4-x) species are presented.

The investigation of the electronic structure and molecular properties of doubly charge transition metal helides is presented. Basic sets are developed for the first row transition metals for this purpose.

The molecular structure of aluminum trihalides AlX3 (X = Cl, Br, I) was determined using gas-phase electron-diffraction data and the results of ab initio molecular orbital and normal coordinate computations. The structure of the chloride and bromide dimers Al2Cl6 and Al2Br6 was also determined. The vibrational force fields of all compounds were then examined, with theoretical and empirical results being compared and discussed.

Research was conducted to examine the molecular geometries, vibrational frequencies and bond dissociation energies of cerium tri- and tetrahalides CeX3 and CeX4 using relativistic effective core potential quantum chemical investigations. All calculations were carried out using the HONDO95.3 code on IBM-SP and Cray C90 computers. Results indicate that pyramidal structures are found for CeF3 for any of 4f1 state at all levels of theory.

The origin of the conduction band in silver halides could have consequences for the understanding of the photographic process. A study was therefore conducted to calculate the electronic structure of the photographic compound AgCl. It will demonstrate that the conduction band has, in fact, a large anion character. The nature of this band would provide a possible explanation about why single interstitial Ag atoms are not stable and why the minimum size of a silver metal cluster, to be stable and developable, is three or four atoms.

The heterogeneous reactions of HOBr with solid crystalline NaCl (HOBr(g) + NaCl(s) -> BrCl(g) + NaOH(s)) and KBr (HOBr(g) + KBr(s) -> Br2(g) + KOH(s)) substrates were investigated at ambient temperature using a Teflon-coated Knudsen cell reactor. The HOBr reactivity was measured using grain, powder and spray-deposited salt substrates. Experimental results showed an uptake probability that is dependent on the total external surface area of the salt substrates.