Synthesis and crystal structure of a noncentrosymmetric form of potassium strontium monovanadate KSrVO4

Transparent single crystals of KSrVO4 were grown at 1500°C by the direct melt and slow cooling technique. X-ray crystallography has shown that this compound crystallizes in the orthorhombic system with the space group P212121 (No. 9). The lattice parameters are a = 5.865, b = 7.491, c = 10.021 Å, and Z = 4. The structure is isotypical with β-K2SO4, but with a different space group. It can be regarded as made of independent [VO4]3− tetrahedra arranged in such way as to delimit large cavities where Sr2+ and K+ are located in eight- and ninefold coordination spheres, respectively. The mean interatomic distances K–O, Sr–O, and V–O are equal to 2.952, 2.645, and 1.720 Å, respectively.