Optical Absorption of MnI2

Abstract
The absorption spectra of single crystals of MnI2 in the region 10000 to 30000 cm−1 are reported. At low temperature, 5 K, several of the observed absorption bands show well‐resolved vibronic fine structure. The absorption bands are assigned to electronic transitions of the d electrons of the manganese ion. From the spectra the values of the ligand field splitting 10Dq = 6400 cm−1 and the Racah parameters B = 640 cm−1, C = 3136 cm−1 are calculated. The results are compared with data for MnCl2 and MnBr2, and are discussed in terms of the covalency in the manganese halides.