COUPLING OF THE NU(7) CH STRETCH WITH RING MODES IN S(1) BENZENE

The coupling of CH stretch to ring motion has been probed in S1 benzen e by analysing the 7(1) dispersed fluorescence spectrum. The spectrum reveals a number of extra bands which arise from vibrational state mix ing occurring in the excited electronic state. The restrictive selecti on rules associated with vibrational coupling and with the spectroscop y of benzene allow identification of the coupled levels. The assignmen ts of these coupled levels are presented and the modes involved in the coupled levels assessed to search for selectivity of particular modes in the coupling. It is concluded that there is no particular selectiv ity among the ring modes that couple to nu7'.