Paramagnetic defects in neutron-irradiated α-quartz: Novel Al-associated E’ centers

Two new paramagnetic defects ( and ) have been revealed in neutron-irradiated natural -quartz by using electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra of the center as well as a previously reported but incompletely characterized center demonstrate that their super-hyperfine structures arise from interaction with 27 Al, the first-ever examples of Al-associated centers in crystalline quartz. The matrices g and , of , g and of the center, have been determined.