The influence of benzene rings on aromatic pathways in the porphyrins



Magnetically induced current density for tetraazaporphyrins (H2ATP), phthalocyanine (H2Pc), and tetrabenzoporphyrin (H2TBP) molecules has been computed. The calculated current strengths for H2ATP and H2TBP were found to be close to these of free base porphyrin (27 nA/T). The current strengths appeared to have greater value than the same ones for H2Pc (21.7 nA/T). The joining of benzene rings to free base porphyrin and to H2ATP causes to appear the additional weak ring current densities. The H2Pc have a degree of aromaticity less than porphyrins according to magnetic criterion. © 2013 Wiley Periodicals, Inc.