This grant, part of the Experimental Physical Chemistry Program, is for the partial support of the XVIII Informal Photochemistry Conference to be held in Santa Monica, CA Jan 9-12, 1989. This conference will concentrate on the photophysics and photochemistry of clusters and weakly bound complexes, high levels of vibration-rotation excitation and radiationless transfer, vector and tensor properties of photodissociation, and transition states and short lived resonances. The funds supplied by NSF will be used to partially support the travel and living expenses of the graduate students and postdoctorals attending the conference.