Abstract

Reaction of Na2S and Cu3VS4 at 1173 K, under a sulfur atmosphere, results in the formation of Na2Cu3VS4. It crystallizes in the trigonal space group P3? (147); a= 3.862(1)Å , c= 6.822(4)Å in a layered structure with the alkali metal ions located between sulphur layers. It is demonstrated that, under the described experimental conditions, the vanadium atoms act as the redox center, which enables the reaction to occur. © Gauthier-Villars.