HIGH-MOBILITY IONS IN THE VISCOUS HYDROCARBON SQUALANE

Pulsed radiolysis, laser flash photolysis, and de photoconductivity we re used to measure the rates of ion-molecule reactions in the viscous hydrocarbon squalane (2,6,10,15,19,23-hexamethyltetracosane). It was f ound that squalane radical cation (hole) is scavenged with a rate cons tant similar to(5-7) x 10(9) mol(-1) dm(3) s(-1), which is 4-10 times faster than other charge transfer reactions in squalane. In this sense , squalane is similar to cyclohexane, methycyclohexane, and decalins, yielding high-mobility ions (HMIs) on radiolysis. While in squalane th e hole is more mobile than molecular ions, its mobility (estimated as 2 x 10(-4) cm(2)/(V s)) is much lower than that of the HMIs in cycloal kanes. The lifetime of the squalane hole in the absence of scavengers is 20 +/- 5 ns.