ANOMALOUS LIFETIME SHORTENING OF S1 TRANS-STILBENE IN CARBON-TETRACHLORIDE AS REVEALED BY PICOSECOND TIME-RESOLVED RAMAN, ABSORPTION, AND FLUORESCENCE SPECTROSCOPIES

The lifetime of the first excited singlet state of trans-stilbene (S1 tSB) in carbon tetrachloride at room temperature is determined to be 3.1+/-0.2 ps with the use of time-resolved Raman, absorption, and fluorescence spectroscopies. The lifetime of 3.1 ps is shorter than the shortest value ever reported by an order of magnitude. The steady state photoirradiation of tSB in carbon tetrachloride shows that the decomposition of the tSB molecule is the primary cause of the lifetime shortening.