The influence of benzene rings on aromatic pathways in the porphyrins

摘要

Magnetically induced current density for tetraazaporphyrins (H_2ATP), phthalocyanine (H_2Pc), and tetrabenzoporphyrin (H_2TBP) molecules has been computed. The calculated current strengths for H_2ATP and H_2TBP 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 H_2Pc (21.7 nA/T). The joining of benzene rings to free base porphyrin and to H_2ATP causes to appear the additional weak ring current densities. The H_2Pc have a degree of aromaticity less than porphyrins according to magnetic criterion.