Simulating the structureless emission bands of Mn2+ ions in ZnCO3 and CaCO3 matrices by means of quantum chemistry

Abstract

Results from theoretical studies on the structureless luminescence spectra of Mn2+ impurity ions in matrices of calcite (CaCO3) and smithsonite (ZnCO3) are reported. The positions of the maxima and the width of the 4 T 1(4 G) → 6 A 1(6 S) emission bands of the indicated luminophors are calculated using a combined approach based on the periodic and cluster methods of quantum chemistry, and on well-known models of the vibrational broadening of electronic transition bands of impurity centers in crystals. The calculated parameters of the spectral bands are compared with the known experimental data and discussed in terms of the structural features of the investigated matrices and the contribution from lattice vibrations in the mechanism of broadening.