Theoretical study of the strong intramolecular hydrogen bond and metal–ligand interactions in group 10 (Ni, Pd, Pt) bis(dimethylglyoximato) complexes

The structural and bonding characteristics of the bis(dimethylglyoximato) complexes of group 10 transition metals ([M(dmg)2], where M = Ni, Pd and Pt) were investigated by means of quantum chemical computations. The equilibrium geometries, energetic and bonding properties were computed using the B3P86 exchange-correlation density functional in conjunction with a 6-311+(+)G∗∗ basis set. The computations revealed that the strong O−⋯H–O hydrogen bond exists only in the presence of the metal cations. The free (dmg)22− ligand has significantly different geometry in which the O−⋯H–O interaction is replaced by N⋯O–H bonds. The characteristics of the metal–ligand interactions were determined by natural bond orbital analysis.