Spectroscopic properties of Nd3+ doped NaLa0.5Gd0.5(WO4)2 crystals

Abstract The absorption spectra of Nd 3+ ions in NaLa 0.5 Gd 0.5 (WO 4 ) 2 :Nd single crystals were registered in the temperature range 4.5–300 K. The crystal-field energy level scheme for the IR and visible multiplets was derived. The intensity parameters Ω t ( t =2,4,6) were determined by the Judd–Ofelt method. The Nd 3+ ion in the titled compound as well as in other double tungstates possesses much higher values of the oscillator strength for the hypersensitive transition 4 I 9/2 → 4 G 5/2 and of the intensity parameter Ω 2 . This fact was tentatively assigned to the lowering of the S 4 symmetry of regular Nd 3+ site to the C 2 one.