Energy levels of Er³⁺in Cs₂NaErCl₆

Abstract

The analysis of the energy level data available for Cs2NaErCl6 is given, the mean error in fitting 31 levels being 16·4 cm-1. The eigenvectors obtained from the calculation are used to compute spontaneous emission probabilities and line intensity ratios for the 4 I 13/2 → 4 I 15/2 magnetic-dipole transitions of Er3+ in Cs2NaErCl6. The liquid-helium-temperature infrared luminescence spectrum for this transition of ErCl3- 6 in cubic elpasolites is reported for the first time and the line locations and relative intensities are in agreement with calculation.