Mechanism of induced circular dichroism of amino acid ester-porphyrin supramolecular systems. Implications to the origin of the circular dichroism of hemoprotein

Host-guest combination influences the circular dichroism (CD) spectra of amino acid ester-porphyrin supramolecular systems. Observation of induced CD requires the presence of intermolecular hydrogen bonding to the carbonyl group of the guest molecule. Molecular orbital calculations show the influence of relative geometry or the carbonyl group and porphyrin plane on the induced CD of the system. Coupling of electric and magnetic transition dipole moments of the carbonyl group with the electric transition dipole moment of the porphyrin Soret bond influences the observed induced CD.