The Vibrational Spectra of the Boron Halides and their Molecular Complexes. Part 8. Ab initio Studies of the Complexes of Boron Trifluoride with Water and Hydrogen Sulphide

The structures, interaction energies and vibrational spectra of the van derWaals complexes formed between boron trifluoride, as Lewis acid, and water and hydrogen sulphide, as Lewis bases, have been determined by means of ab initio calculations at the second-order level of Møller-Plesset perturbation theory, using a number of basis sets, including double- and triple-zeta, with polarization and diffuse functions.Two conformers, an eclipsed and a staggered species, have been examined for each complex. In the case of the boron trifluoride-water complex, the spectra computed using the largest basis set have been compared with the spectra obtained experimentally in nitrogen, argon and neon matrices at cryogenic temperatures.KEYWORDS: Ab initio calculations, molecular complexes, boron trifluoride, water; hydrogen sulphide, molecular structures, interaction energies, vibrational spectra