Paramagnetic relaxation of cyclohexane radical cation in solution as measured by the method of time-resolved magnetic field effect

Abstract

The method of time-resolved magnetic field effect was applied to measure the spin–lattice relaxation time T₁ for radical cations of a number of cycloalkanes in n-hexane solution at room temperature. The T₁ value for the Jahn–Teller active cyclohexane radical cation was found to be approximately 9 ns which was substantially shorter than typical values for organic radical ions. Based upon the similarity of effects that various factors had on the spin–lattice relaxation rate of the cyclohexane radical cation and the benzene radical anion it was proposed that the spin–orbital interaction made the predominant contribution to the relaxation of both radicals.