Calculation of the electronic structures and the gas-phase heats of formation of BH3,NH3 and BH3,CO

Abstract

The electronic structures and energies of the two complexes BH₃,NH₃ and BH₃,CO and their donor and acceptor components have been investigated by using basis sets of Gaussian-type atomic orbitals. The calculated heats of formation in the gas-phase of the two complexes are in satisfactory agreement with experimental data. The equilibrium B–N bond length in BH₃.NH₃ is 1·665 Å and the energy barrier to rotation of the groups around it is 2·47 kcal. mole^–1. In this complex the BH₃ and NH₃ moieties are staggered with respect to each other. The σ-reorganisation energy of BH₃ is calculated to be 14·5 kcal. mole^–1.