Electron spin-echo modulation for a ‘1 + 2’ pulse train in a weak hyperfine interaction limit

An analytical description of nuclear modulation for the ‘1 + 2’ electron spin-echo pulse train is derived using the approximation of extremely weak electron-nuclear interaction. Experimental data which were obtained for a model system of hydroquinone radicals stabilized in a frozen solution of phosphoric acid are found to be in good agreement with the calculations. Based on these results a new method of data acquisition is proposed, which allows one to use a ‘1 + 2’ pulse train in 2D format, as a substitute of stimulated echo, which has improved modulation amplitude.