The vibrational spectra of the boron halides and their molecular complexes: Part 7. Ab initio predictions of the infrared spectra of the complexes of boron trifluoride with some linear nitrogen donors

Abstract

The infrared spectra of the 1:1 molecular complexes of boron trifluoride with five linear nitrogen-containing electron donors (nitrogen, hydrogen cyanide, cyanogen fluoride, cyanogen and cyanoacetylene) have been computed by means of a series of ab initio molecular orbital calculations, at the second order level of Møller–Plesset perturbation theory, using the 6-31G∗∗ basis set. This work extends the calculations of the structures, energetics and Mulliken atomic charges of the same series of complexes, reported earlier. The vibrational properties, specifically the complex–monomer wavenumber shifts and the B⋯N stretching and BF3 librational wavenumbers and their associated force constants, have been correlated with the computed interaction energies, corrected for basis set superposition error and for zero-point energy difference.