MOLECULAR-ORBITAL STUDIES OF NIDO-BERYLLABORANES, B5H10BEX, WHERE X IS BH4, B5H10, CH3, OR C5H5

Molecular orbital studies are presented at the minimum basis set level for the beryllaboranes B5H10BeBH4, B5H10BeB5Hl0, B5H10BeCH3, and B5H10BeC5H5. The method, nearly at the SCF level, employs the prddo (partial retention of diatomic differential overlap) program. The bonding is analyzed in terms of charge stability, static reactivity indices, degrees of bonding, overlap populations, and fractional bonds obtained from localized molecular orbitals by using the criterion of Boys. The bonding within B5H10 units is remarkably similar, although bonding about Be in B5H10BeC5H5 differs significantly from that in the other compounds. The relationships of these studies to the NMR spectra and to related chemistry are briefly indicated. © 1979, American Chemical Society. All rights reserved.