The structures and bonding of pi-complexes formed by the completely inorgan
ic ring systems B2N2R4 and B2N3R4- have been investigated using density fun
ctional calculations. These rings are isoelectronic with cyclobutadiene and
the cyclopentadienyl anion, respectively and a detailed comparison of thei
r bonding characteristics is described. The optimized structure of (eta(5)-
B2N3H4)(2)Fe, a fully inorganic ferrocene analogue, is reported. (C) 1999 E
lsevier Science S.A. All rights reserved.