Theoretical study on methelated porphyrin

Porphyrins and their derivatives are ubiquitous in biology. Many of them , such as chlorophylls, haemoglobin, and cytochromes, are essential in biocatalytic reactions. All of these molecules share in common the porphyrin macrocyclic substructure, consisting of a conjugated ring of four pyrrole subunits. Among various molecular wires synthesized so far porphyrin molecules have attracted much attention due to their extremely small HOMO–LUMO energy gaps They have been found to assume planar structures and be stable in air. We compute and calculated HOMO and LUMO of H2P and methyl porphyrin at AM1 level of theory.