Studies of geminate ion recombination and formation of excited states in liquid n-dodecane by means of a new picosecond pulse radiolysis system

Abstract

A new ps pulse radiolysis system for optical absorption spectroscopy from visible to infrared regions was developed to investigate the primary processes of radiation chemistry. 10 ps electron pulses from a 28 MeV electron linac and ps diode lasers were used as irradiation source and analyzing light, respectively. The ps diode lasers were synchronized with the electron pulses. The time profile of the absorption was obtained by changing the time difference between the electron and the laser pulses. The time resolutions of the system were a few tens ps. The time-dependent behavior of the cation radicals, electrons and excited states in primary processes in liquid n-dodecane was studied by using the new system. The decays of the cation radicals and electrons showed the geminate ion recombination based on the diffusion theory in the time region within 2 ns.