Bonding in titanocenyl complexes containing O,O′‐cyclic ligands

Density functional theory calculations show that the formal 16‐electron count of d⁰ Cp₂Ti^IV(O,O′‐BID)]^0/1 complexes containing a O,O′‐chelated bidentate ligand O,O′‐BID of different ring size, is increased via Ti←O π bonding when both the O donor atoms carry a formal negative charge. The Ti←O π bonding occurs by symmetry lowering of the complex by either symmetrical (C_s) or unsymmetrical (C₂) folding of the O,O′‐BID ligand round the O···O axis. An NBO analysis confirms the Ti←O π charge transfer via back‐bonding. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010