PUB - Publikationen an der Universität Bielefeld

Bonding in tetraphosphabicyclo[3.3.0]octa-1,4-diene-1,4-diolate dilithium is investigated by means of ab initio calculations at the RHF level. A population analysis of the resulting wavefunction in terms of the natural bond populations indicates that (a) the d-orbital population at phosphorus does not play a dominant role in the determination of bonding in the bicyclic system and (b) there is a transfer of charge density from the bridgehead atoms to the oxygen atoms. This causes a shortening of the central PP bond and can be rationalized qualitatively within the model of Dewar-Chatt-Duncanson.