Electronic structure of aminoborane: a comparison between non-empirical and semiempirical theoretical methods

Abstract

The electronic structure of aminoborane, BH₂·NH₂, has been calculated ab initio by use of extended basis sets of Gaussian-type orbitals. The binding energy (corrected for correlation) is 550 kcal. mole^–1 and the energy of rotation about the B–N bond is 40·7 kcal. mole^–1. The B–N bond is polar in the sense [graphic omitted] and the calculated dipole moment of the molecule is 2·071 D. The highest bonding orbital is of σ type with energy –12·0 eV. Extended Hückel calculations on the same compound give orbital energies which agree fairly well with those above whilst the charge distribution can be reproduced by the CNDO method. However neither of the semiempirical techniques yield good overall agreement with the ab initio calculations.