STUCTURE AND BONDING OF NITROSYL METALOPORPHYRIN COMPLEXES

Robbie Davis

John Graham

Department of Physical Science

The structures of Iron (II), Iron (III), Cobalt (II) and Manganese (II) nitrosyl porphyrin complexes were optimized using the Gaussian 03W program. Calculations were performed at various levels of theory and with different basis sets up to the BPW91/6-31G(d) level. Optimized geometries are compared to those predicted previously by a series of single point density functional calculations. The nature of bonding between the metal and nitrosyl ligand is discussed with regard to molecular orbital analysis, structural features and relative N-O stretching frequencies. The results are compared to previously published data resulting from Fenske-Hall approximate molecular orbital calculations.