Synthesis, crystal structure, and electronic structure of RbVSe2

摘要

RbVSe2 has been synthesized at 773 K through the reaction of V and Se with a Rb2Se3 reactive flux. The compound crystallizes in the orthorhombic space group D-2h(24)-Fddd with 16 formula units in a cell of dimensions a = 5.6724(9)angstrom, b = 13.648(2) angstrom, and c = 24.181(4)angstrom, at T = 153 K. The structure possesses infinite one-dimensional (1)(infinity)[VSe2-] chains of edge-sharing VSe4 tetrahedra separated from the Rb+ ions. These (1)(infinity)[VSe2-] chains distort slightly to (1)(infinity)[V(1)V(2)Se-4(2-)] chains. The V-V distance within these chains is 2.8362(4)angstrom. First-principles total energy calculations indicate that a non-magnetic configuration for the V3+ cations is the most stable. (c) 2005 Elsevier Inc. All rights reserved.