Electron spin echo envelope modulation spectroscopy (ESEEM) of the radical cations of 14N and 15N bacteriochlorophyll a

Abstract

An electron spin echo envelope modulation frequency analysis is performed of the 14N and 15N bacteriochlorophyll a + cation in solid solution. Hyperfine couplings of 2.0 and 3.1 MHz are derived which correspond to the perpendicular component of the axial hyperfine coupling tensor. Seven quadrupole frequencies were measured, six of which group in two sets of three zero-field quadrupole splittings.