Recombination dynamics of photodissociated I 2 2 in size selected Ar and CO 2 clusters
نویسندگان
چکیده
We report time-resolved photodissociation and geminate recombination dynamics of I2 2 in size-selected I2 Arn and I2 ~CO2!n cluster ions by using ultrafast pump–probe techniques at 790 nm in conjunction with a tandem time-of-flight mass spectrometer. The absorption recovery, which reflects the time scale for photodissociation followed by recombination and vibrational relaxation of I2 2 inside the cluster, shows a strong dependence on the composition of the surrounding cluster solvent. The absorption recovery time for I2 ~CO2!16 is ;1 ps, whereas for I2 Ar20 it is ;130 ps. This difference is discussed in terms of electrostatic and hard sphere interactions. We also observe the time dependence of the destruction of the Ar solvent cage for I2 Ar16 . Finally, absorption recovery data for I2 ~CO2!n cluster ions taken with 790 nm pump–probe wavelengths are compared with the greater energy release 720 nm data. © 1997 American Institute of Physics. @S0021-9606~97!01304-4#
منابع مشابه
A combined experimental/theoretical investigation of the near-infrared photodissociation of IBr- (CO2)n.
We report the collaborative experimental and theoretical study of the time-resolved recombination dynamics of photodissociated IBr(-)(CO(2))(n) clusters. Excitation of the bare anionic chromophore to the dissociative A(') (2)Pi(1/2) state yields only I(-) and Br products. Interestingly, however, the addition of a few solvent molecules promotes recombination of the dissociating chromophore on th...
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