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'.