Abstract
An optical study of pressure induced (0-7 kbar) dynamic and structural changes associated with a pentacene guest in a p-terphenyl host crystal at low temperature (2-15 K) is presented. Low temperature absorption, time-resolved emission, and photon echo data have been obtained. We observe local structural changes of the host matrix, site specific changes in intersystem crossing rates, and the effect of pressure on the homogeneous optical dynamics of pentacene in p-terphenyl.