We report a femtosecond time-resolved photoelectron spectroscopy (TRPES) investigation of internal conversion in the first two excited singlet electronic states of styrene. We find that radiationless decay through an S 1 /S 0 conical intersection occurs on a timescale of ~4 ps following direct excitation to S 1 with 0.6 eV excess energy, but that the same process is significantly slower (~20 ps) if it follows internal conversion from S 2 to S 1 after excitation to S 2 with 0.3 eV excess energy (0.9 eV excess energy in S 1 ).

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