Alpha barium zinc cadmium sulfide phosphors and method
New phosphors which may be activated to luminesce in the red to green portion of the spectrum have an alpha crystal structure isostructural with Ba.sub.2 MnS.sub.3 and the composition Ba.sub.2 Zn.sub.1.sub.-y Cd.sub.y S.sub.3 : A.sub.w.sup.. zZnS wherein A is an activator element selected from the group consisting of manganese, europium, cerium, lead and terbium, y is a numerical value in the range from 0 to 1, z is a numerical value in the range from 0 to 20, and w is a numerical value in the range from 0.00001 to 0.1. Methods of making these phosphors are described.