Ion—molecular charge transfer as studied by the method of optically detected ESR of radical pairs

Effects of ion—molecular charge transfer upon optically detected (OD) ESR spectra of radical pairs have been studied experimentally and theoretically. Theoretical analysis has shown that under certain conditions (often realized in experiments) OD ESR spectra are analogous to standard ESR ones. Broadening and collapse of the hyperfine structure (exchange broadening) have been observed experimentally depending on the concentration of neutral acceptors. Ion—molecular charge transfer rate constants have been calculated for some radical-anions from the experimental data.