SPATIAL-DISTRIBUTION OF LOCALIZED-ELECTRONS PRODUCED DURING THE LASERPHOTOIONIZATION OF ANTHRACENE IN LIQUID METHYLCYCLOHEXANE

Kinetics of the geminate recombination of electron-ion pairs in an ant hracene solution in methylcyclohexane was studied by means of photoass isted ion pair separation at a picosecond time resolution. Ion pairs w ere produced by two-photon ionization of anthracene with 360-nm and 27 0-nm UV pulses followed by a 1080-nm IR pulse. The observed kinetics o f photocurrent decay with increasing the delay between UV and IR pulse s was in agreement with both the diffusion model of electron motion an d the Gaussian form of distribution by initial distances between an el ectron and the parent anthracene cation, f(o)(r> = (pi B-2)(3/2)exp(-r (2)/B-2) with B = 4.0 +/- 0.5 and 7.1 +/- 1 nm for excitation at 360 a nd 270 nm, respectively.