Electron spin resonance study of octane radical cations in irradiated pentane matrices

ESR spectra of octane radical cations have been obtained by irradiating pentane matrices, containing octane and 2-chloropentane as additives, and by taking the difference spectrum by computer between the spectra before and after (selective) removal of the octane radical cations by illumination. The spectrum of octane radical cations consists of a single unresolved line; the width of the line is mainly due to unresolved Fermi-contact hyperfine interaction with hydrogen (or deuterium) nuclei of the radical cation and of adjacent matrix molecules. Fermi-contact hyperfine interaction with hydrogen (or deuterium) nuclei of the matrix is attributed to the formation of a charge-transfer complex between octane radical cations and matrix molecules