Electronic structure of bis-azepine transition-metal complexes: A DFT investigation

DFT calculations with full geometry optimizations have been carried out on a series of hypothetical compounds of M(C6NH7)2 (M = transition metal) type with an eclipsed and staggered conformations in order to understand their electronic structure. A rationalization of the bonding with respect to the electron count in all the investigated hypothetical complexes is provided. Depending on the electron count and the nature of the metal, the azepine ligands can bind to the metal through the (η7,η7), (η6,η6), (η7,η4), (η6,η4), (η4,η4), (η4,η2) and (η3,η3) coordination modes.