The Excited States of Covalently-Linked Dimeric Porphyrins; Part 1: The Excited Singlet States
Chow, Y.F.A., David Dolphin, Paine, J.B. III, McGarvey, D., Pottier, R., and Truscott, T.G.
J. Photochem. Photobiol., B. Biol.
The ground state absorbance and emission properties of a series of covalently linked biporphyrins (I, n = 0-8) were studied in both their neutral and dicationic forms. The fluorescence quantum yields are comparable in value with that obtained from hematoporphyrin IX. Soret band splitting is observed for porphyrin rings separated by a hydrocarbon chain containing 0-3 C atoms joined at the β,β' ring positions. The biporphyrin linked directly at the meso position shows considerable steric hindrance and behaves like 2 independent chromophores.