LUMINESCENCE PROPERTIES OF NI2+ IN CSCDBR3

Spectroscopic properties of Ni2+ ions substituted in the unidimensional compound CsCdBr3 were investigated from 9 to 300 K. The structured features of the absorption spectrum have been interpreted on the assumption of a trigonal distortion of the Ni2+ site. Four emissions were observed and assigned to the 1T2 --> 3T2, 3T1, 1E and to the 3T2 --> 3A2 transitions in order of decreasing energy. Energy-level calculations were performed in the usual cubic model and the results compared to the values obtained in a trigonal-field framework. The lifetimes have been measured and fitted by the Mott law and using the Struck and Fonger model.