Figure 3

Crystallographic structure of Sr2–xCaxNiWO6 (x = 0.02). Large yellow spheres, small blue spheres, small purple spheres, small green spheres and red spheres indicate Sr2+, Ca2+, Ni2+, W6+ and O2- ions respectively.

Crystallographic structure of Sr2–xCaxNiWO6 (x = 0.02). Large yellow spheres, small blue spheres, small purple spheres, small green spheres and red spheres indicate Sr2+, Ca2+, Ni2+, W6+ and O2- ions respectively.