Luminescence Properties of Double Molybdates and Tungstates of Rare Earth and Alkali Metals.

A study was made of the luminescence properties of individual compounds and solid solutions of composition M//5'Eu//xLn//1// minus //x(M** double prime O//4), M//5'Tb//xLn//1// minus //x(M double prime O//4)//4 (M double prime multiplied by Mo,W; M prime equals Na,K; Ln multiplied by Gd,Y; x equals 0. 1-1. 0) and M prime Eu//xLn//1// minus //x(M double prime O//4)//2, M prime Tb//xLn//1// minus //x(M triple prime O//4)//2 (M prime equals Li,Na,K,Cs). It was found that double molybdates and tungstates of rare earth and alkali metals possess a weak concentration quenching up to an 80% activator concentration, have a linear current characteristic of the luminescence brightness (in the range of values from 0. 1 to 100 mu A/cm**2), and have high radiation stability.