Rietveld Refinement and Magnetic Properties of Polycrystalline (Ba,K)VSe3 and BaV(S,Se)3

The quasi-one-dimensional hexagonal perovskites BaVS3 and BaVSe3 are susceptible to doping under high pressure. In this study, barium was replaced with potassium, and mixed chalcogenides BaV(S,Se)3 were stabilized at high pressure. Hexagonal BaVSe3 undergoes a tetragonal distortion on doping with K. Magnetic moments decrease, possibly due to decreasing magnetic interactions between the vanadium atoms. The lattice constants of BaV(S,Se)3 change linearly with Se content, indicating that S and Se can be mixed in any ratio. Deviation from BaVSe3 stoichiometry decreases the intrinsic coercive force of the material.