Abstract

Octatetraene can be photoisomerized even when it is incorporated in a low temperature n-hexane crystal. When this is done by irradiating the zero-phonon component of the S₀→S₁ origin band with a single frequency laser, very narrow (less than 10 MHz) persistent holes can be burned. We have determined the effect of an externally applied electric field on these persistent holes and fit the observed data with a simple quantum mechanical model parameterized in the S₀→S₂ and S₁→S₂ transition dipoles and the projection of the local electric field on the octatetraene chain axis. The magnitude of the local electric field (ca. 10⁶ V/cm) is only consistent with one of the three possible n-hexane sites that could have accomodated the octatetraene guest.

© 1992 Optical Society of America