Real-time detection of S(1D2) photofragments produced from the 1B2(1Σu+) state of CS2 by vacuum ultraviolet photoelectron imaging using 133 nm probe pulses

Ultrafast photodissociation dynamics from the B-1(2)((1)Sigma(+)(u)) state of CS2 are studied by time-resolved photoelectron imaging using the fourth (4 omega, 198 nm) and sixth (6 omega, 133 nm) harmonics of a femtosecond Ti: sapphire laser. The B-1(2) state of CS2 was prepared with the 4 ! pulses, and subsequent dynamics were probed using the 6 omega vacuum ultraviolet (VUV) pulses. The VUV pulses enabled real-time detection of S(D-1(2)) photofragments, produced via CS2 *(B-1(2)((1)Sigma(+)(u))) -> CS(X-1 Sigma(+)) + S(D-1(2)). The photoionization signal of dissociating CS2*(B-1(2)((1)Sigma(+)(u))) molecules starts to decrease at about 100 fs, while the S(D-1(2)) fragments appear with a finite (ca. 400 fs) delay time after the pump pulse. Also discussed is the configuration interaction of the B-1(2)((1)Sigma(+)(u)) state based on relative photoionization cross-sections to different cationic states. Published by AIP Publishing.