Optical Properties of HgS and HgS:$Co^{2+}$ Crystals

Abstract

Melt-grown crystals of HgS and HgS:Co2+ were used to measure their optical absorption spectra. The optical energy band gaps of these crystals were 2.030 eV and 1.870 eV at room temperature, respectively. The impurity optical absorption peaks of Co2+ were observed at 4030, 5988, 12285, 12672, and 12905 cm-1. These peaks can be attributed to the electronic transitions between the split energy levels of Co2+ ion located at the T(d) symmetry site, where the crystal field, Racah, and spin-orbit coupling parameters were given by Dq = 403, B = 427, and lambda = -155 cm-1, respectively.