Model calculations on hydrocarbon radiolysis. Part 1.—Spin correlation effects in pure alkanes

Abstract

A computer model is described which uses Monte Carlo methods to simulate the processes occurring in spurs produced by the radiolysis and VUV photolysis of liquid hydrocarbons. The independent-pairs approximation is used to simplify the treatment of the dynamics. Electron spin is treated explicitly: it is assumed that the overall spin state of the spur is singlet initially and remains so. For reactions between radicals and radical ions, radical quenching of triplet states, triplet–triplet annihilation etc., the spin state of the reactants is evaluated and used to choose the products formed. The model is applied to formation of radicals, alkenes and excited states in alkanes: it is shown that spin correlation plays a major role.