THE VIBRATIONAL-SPECTRA OF THE BORON HALIDES AND THEIR MOLECULAR-COMPLEXES .2. AB-INITIO PREDICTIONS OF THE STRUCTURE AND VIBRATIONAL-SPECTRA OF THE BORON-TRIFLUORIDE DIMER

A series of ab initio molecular orbital calculations has been performed on a number of isomers of the dimer of boron trifluoride, at the Hartree-Fock level of theory and using the 6-31G* split-valence polarized basis set, in order to identify the most probable structure of this dimer and to predict the wavenumbers and band intensities of its infrared and Raman spectra. We conclude that the minimum energy structure consists of two boron trifluoride monomer units which retain the planarity of the monomer species, the two planes lying parallel to one another in a centrosymmetric arrangement of C2h symmetry. The results will be used in an analysis of some new infrared data obtained for samples of this species isolated in argon and nitrogen matrixes.