A novel ternary alkali-halide crystal is reported. We obtain the F ban
d, which reveals an electron trap associated with a definite lattice c
onstant, confirmed by X-ray diffractometry. Vegard's law and a Mollwo-
Ivey type relation are generalized for a ternary mixed system. Raman s
pectra for a sample are shown, indicating crystalline inhomogeneity. (
C) 1998 Elsevier Science B.V.