Crystal structure of Ca1.29Bi0.14VO4

Abstract

The structure of a single crystal, grown by a slow cooling a melt of Ca1.29Bi0.14VO4 composition, was analyzed. The crystals belong to the rhombohedral space group R3c and the dimensions of the unit cells are a = 10.848(1) Å, c = 38.048(6) Å, V = 3877.6(8) Å3 for the pale yellow crystal, and a = 10.857(1) Å, c = 38.063(6) Å, V = 3885.6(8) Å3 for the yellow crystal, respectively. Unit cell dimensions of the crystal were larger than those of the host crystal, Ca3(VO4)2, owing to the Bi that replaced Ca in the unit cell. Ca in the unit cell formed six, eight and nine coordinated polyhedra with O atoms and Bi replacing Ca entered the eight or nine coordinated Ca sites with different crystallographic environments in the unit cell. All the V in the unit cell formed four coordinated tetrahedra with O atoms, however V-O bond lengths in the tetrahedra were different from one another.