Cis-trans photoisomerization of a p-styrylstilbene, a one- and twofold adiabatic process

Article abstract of DOI:10.1021/ja00164a031

The mechanism of the Z/E photoisomerization of a p-styrylstilbene has been studied by steady state and time-resolved fluorescence measurements combined with isomerization quantum yield determinations. It was found that on excitation of the Z,Z isomer both the isomers, Z,E and E,E, are produced initially, mainly by adiabatic processes on the singlet excited surface. Quantum mechanical calculations give surface profiles supporting the adopted mechanism.