ELECTRON PARAMAGNETIC RESONANCE IN GEM QUALITY ZIRCON

The electron paramagnetic resonance spectra of the natural single crystal of the tetragonal structure zircon containing impurity Gd 3+ have been measured. The fine structure parameters were calculated using a least-squares fitting procedure. The hyperfine structure for odd isotopes 155 Gd and 157 Gd was clearly resolved, and the values of the hyperfine coupling constant to first order were given.