PHOTON-GATED PHOTOCHEMICAL HOLE-BURNING BY ELECTRON-TRANSFER REACTION- ZINC TETRATOLYLTETRABENZOPORPHINE IN POLY(CHLOROMETHYLSTYRENE)

We report a new photon-gated photochemical hole burning system involvi ng a donor-acceptor electron transfer reaction in which the electron a cceptor, i.e. a Cl atom, is directly bonded to the matrix polymer chai n in each monomer unit, namely zinc tetratolyltetrabenzoporphine (ZnTT BP)/poly(chloromethylstyrene) (PCMS). The simultaneous irradiation by an Ar+ laser in conjunction with a dye laser forms holes 70 times more efficiently than irradiation by the dye laser alone for this ZnTTBP/P CMS system. The irradiation intensity dependence and the annealing tem perature dependence of the hole depth for a one-colour hole suggest th at the hole formation mechanism for the latter is a non-photochemical process in the PCMS. The quantum efficiency of hole formation by two-c olour irradiation and the gating ratio in PCMS are much larger than th ose found for poly(vinyl chloride).