Electronic Structure and Bonding in Metal Porphyrins and Phthalocyanines

Authors

Meng-Sheng Liao, Utah State University
Steve Scheiner, Utah State UniversityFollow

Document Type

Article

Publication Date

2002

Volume

43

Abstract

A systematic theoretical study of the electronic structure and bonding in metal meso-tetraphenyl porphines MTPP, M=Fe, Co, Ni, Cu, Zn has been carried out using a density functional theory method. The calculations provide a clear elucidation of the ground states for the MTPPs and for a series of [MTPP]x ions (x=2+, 1+, 1−, 2−, 3−, 4−), which aids in understanding a number of observed electronic properties. The calculation supports the experimental assignment of unligated FeTPP as ³A_2g, which arises from the configuration (d_xy)²(d_z2)²(d_xz)¹(d_yz)¹. The calculated M–TPP binding energies, ionization potentials, and electron affinities are in good agreement with available experimental data. The influence of axial ligands and peripheral substitution by fluorine are in accord with the experimental observation that not only half-wave potentials (E_1/2) of electrode reactions, but also the site of oxidation/reduction, may be dependent on the porphyrin basicity and the type of axial ligand coordination.

Recommended Citation

Electronic structure and bonding in metal porphyrins and phthalocyanines S. Scheiner and M.-S. Liao Polym. Prepr. (Am. Chem. Soc., Div. Polym. Chem.) 2002 43 96-97