ZnVSe₂O₇ and Cd₆V₂Se₅O₂₁: New d¹⁰ Transition-Metal Selenites with V(IV) or V(V) Cations

Two new metal selenites with a combination of vanadium(IV) or vanadium(V) cations, namely, ZnVSe2O7 and Cd6V2Se5O21, have been synthesized by hydrothermal and high-temperature solid-state reactions, respectively. The structure of ZnVSe2O7 features a 3D network of vanadium(IV) selenite with 1D tunnels occupied by zinc(II) ions. The 3D network of vanadium(IV) selenite is formed by corner-sharing VIVO6 octahedral chains bridged by selenite groups. In Cd6V2Se5O21, the interconnection of cadmium(II) ions by bridging and chelating selenite groups led to a 3D framework with large tunnels along the b axis, and the 1D chains of corner-sharing VVO4 tetrahedra are inserted in the above large tunnels and are bonded to the cadmium selenite framework via Cd−O−V bridges. Both compounds exhibit broad emission bands in the blue-light region. Results of magnetic property measurements show there is significant antiferromagnetic interaction between V4+ centers in ZnVSe2O7. The electronic structure calculations for both compounds have been also performed.