Supramolecular interactions of meso-tetra-2-chlorophenylporphyrin with fullerenes: A luminescence study

Emission spectroscopic studies were performed to follow the intermolecular complexation of [60]- and [70]-fullerene as well as of o- and p-chloranils with meso-tetra-2-chlorophenylporphyrin (clTP) in non-interacting toluene medium. This has revealed different quenching mechanisms to be operational for these two groups of compounds. The ground state association constants of the intermolecular complexes were determined on the basis of the Stern-Volmer (SV) equation of fluorescence quenching. Theoretical justification for complex formation in terms of charge distribution, HOMO-LUMO interactions were provided in terms of DFT and ab initio Hartree-Fock calculations.