Neutron diffraction study of the crystal structure of rare earth orthovanadites

For refinement of crystallochemical peculiarities of the structure the neutron diffraction study of REVO3 (RE=REE) compounds is carried out. Position ion parameters in orthovanadites, vanadium-oxygen, REE-oxygen distances are determined. The data obtaned permit to trace the tendency to the growth of the degree of covalence of REE-oxygen bond in transition from La to Yb. Experimentally established is the interrelation between the deformation of rare earth polyhedrons as well as vanadium octahedrons and covalence degree of cation-anion chemical bond in rare earth orthovanadites