LONG-LIVED ELECTRONIC-DEFORMATION EXCITATIONS IN A POLYACETYLENE CHAIN - THE PHOTOEXCITATION SPECTRUM

It is observed that the photoexcitation efficiency of neutral long-liv ed states in a trans-polyacetylene chain increases with increasing pho ton energy of the excitation. The observed effect is given an interpre tation according to which the energy of a photon above the optical abs orption edge is added to the excitation of the vibrational subsystem, increasing sharply the probability that the chain relaxes into a long- lived deformed neutral state. (C) 1998 American Institute of Physics. [S0021-3640(98)01010-X].