Predissociation dynamics of the B state of CH3I by femtosecond pump-probe technique.

Opt Express

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei, PR China.

Published: June 2009

The laser induced predissociation dynamics of the B Rydberg state of CH(3)I following two-photon absorption of a pump pulse was studied with femtosecond pump-probe photoelectron imaging coupled with time-resolved mass spectroscopy. The predissociation lifetime was measured to be 1.55 ps induced by the crossing between the B state and the repulsive A-band. Two possible predissociation channels were observed originating from (a) direct coupling between the B state and the repulsive (3)Q(0) state and (b) a second crossing between the (3)Q(0) and (1)Q(1) states after the coupling between the B and (3)Q(0) states, respectively.

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http://dx.doi.org/10.1364/oe.17.010506DOI Listing

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