A DFT investigation of axial N-donor ligands effects on the high valent manganese-oxo meso-tetraphenyl porphyrin

作者：Kavousi Hossein; Rezaeifard Abdolreza^*; Raissi Heidar; Jafarpour Maasoumeh

来源：Journal of Porphyrins and Phthalocyanines, 2015, 19(5): 651-662.

DOI：10.1142/S1088424615500029

• high-valent manganese(V) oxo porphyrin
• nitrogen donors
• density functional theory
• Mn-O bond distance

The effect of different electronic and structural nitrogen donors (L) on the N-(ax)-Mn-O properties in the high valent manganese-oxo meso-tetraphenylporphyrin intermediate is investigated by the density functional B3LYP method with 6-31g* basis set. The geometric structures, frontier molecular orbitals, thermodynamic parameters and physical properties such as chemical potential and chemical hardness of [(TPP)(L)MnO](+) complexes in the gas phase as well as water solution are calculated. Our theoretical results confirm that the Mn-O distances in [(TPP)(L)MnO](+) species decrease by replacing imidazoles with pyridines, amins as well as electron-poor and hindered nitrogen donors resulting from extending the Mn-N-(ax) bonds. These results are supported by vibrational frequencies, atoms in molecules (AIM) and natural bond orbital (NBO) analysis. It is worth mentioning that the co-catalytic activity trend of different nitrogen donors observed experimentally in the presence of title Mn porphyrin is consistent with the calculated Mn-N-(ax) and Mn-O bond lengths in this work.

• 出版日期2015-5