ESR and optical absorption studies of Mn2+ ions doped silica and germania gels

Abstract The results of an investigation of the structure of Mn 2+ ions in silica and germania sol-gels using DTA, ESR and optical absorption techniques are reported. ESR spectra of Mn 2+ doped silica and germania gels at 303 K have a well resolved hyperfine structure of six lines spread over a region of about 50 mT centered at g = 2.003 ± 0.001. The optical absorption spectrum for silica gels heat treated at 573 K shows bands characteristic of Mn 2+ ions in an octahedral symmetry.