Complexation of free-base and 3d transition metal(II) phthalocyanines with endohedral fullerenes H@C60, H2@C60 and He@C60: The effect of encapsulated species

Abstract

We studied theoretically the bonding of unsubstituted free-base phthalocyanine H2Pc and its 3d transition metal complexes MPc (MMn, Fe, Co, Ni, Cu, Zn) with endohedral non-metalofullerenes H@C60, H2@C60 and He@C60, by using PBE functional with Grimme's dispersion correction and DNP basis set. The calculated formation energies, geometries and electronic parameters (energies and distribution of HOMO and LUMO orbitals, electrostatic potential and spin density plots) were analyzed and compared to those of the dyads formed between the same series of unsubstituted Pcs and empty-cage C60. Particular differences were found in MnPc coordination pattern and the resulting frontier orbital distribution.