EPR-SPECTRA OF MN2+ DOPED CDCL2-PBBR2-KL GLASSES

Electron paramagnetic resonance (EPR) spectra of glasses of five compositions: 1. I, (CdCl2)0.3(PnCl2)0.6(KI)0.1; 2. II, (CdCl2)0.3(PbCl2)0.5(KI)0.2; 3. III, (CdCl2)0.3(PbBr2)0.5(KI)0.2; 4. IV, (CdCl2)0.2(PbBr2)0.6(KI)0.2; and 5. V, (CdBr2)0.2(PbBr2)0.6(KI)0.2 doped with MnCl2 and MnBr2 at concentrations from 0.1 to 3.0 mol% were investigated. An intense geff ≊ 2.0 resonance was found in all glasses studied; the other resonances, geff ≊ 4.3 and geff = 3.3, changed their intensities in relation to the geff ≊ 2.0 resonance in dependence on the composition of the host glasses. Most of the magnetically active centres of impurity Mn2+ ions with the geff ≊ 4.3 were assumed to be tetragonally distorted octahedrons that could be described by fourth order spin Hamiltonian. The assumption was supported by temperature behavior of intensities of the geff ≊ 4.3 resonance. The local structure of most of the magnetically active Mn2+ centres in glasses with a higher amount of bromide atoms was supposed to be of lower symmetry than the local structure of centres with chloride atoms. The assumption was supported by decrease of intensity of the geff ≊ 2.0 resonance in relation to the intensity of the other resonances, the geff ≊ 3.3 and the geff ≊ 4.3, in series from chloride through mixed to bromide glasses. The optical spectra of pure and Mn2+ doped glasses were measured from visible to far infrared region and both kinds of spectra were indistinguishable. © 1990.