Bonding in boron hydrides

Abstract

Unique preferred localized valence structures for B2H6, B4H10, B5H11 and B6H10 have been found from accurate self-consistent field wavefunctions by maximizing Coulomb repulsions of electron pairs within orbitals. Objective evidence has thus been obtained for two-centre BH, three-centre bridge BHB, two-centre BB and central three-centre BBB bonds, but not, as yet, for open three-centre BBB bonds. Localization in B5H9 is ambiguous, as it is in organic molecules such as benzene. More thermodynamical stable isomers or plausible reaction pathways appear to have more resonance structures, and less reactive (or more plausible) structures or intermediates appear to have more nearly uniform charge distributions. © 1972, Walter de Gruyter. All rights reserved.