Optical study of Mn2+ ions environments in fluorochlorozirconate and fluorobromozirconate glasses

Some manganese doped fluorozirconate, fluorochloro- and fluorobromozirconate glasses have been prepared following and improving some standard methods. Electron probe microanalysis has been carried out to obtain the actual composition of the samples. The optical properties of Mn2+ ions, including steady state excitation and emission, and luminescence decay have been studied. Values of the crystal field and Racah parameters have been estimated from the excitation data. The results have been interpreted in terms of the progressive substitution of the fluorine ions in the first coordination shell of Mn2+ by chlorine or bromine ions. A concentration of about 6 at% of chlorines or bromines with respect to the total number of halide ions is enough to have most of the Mn2+ ions coordinated to only chlorines or bromines.