THE CRYSTAL STRUCTURES OF POTASSIUM XANTHATES. N.A. Frolova, The University of Irkutsk, Irkutsk, Russia .

By X-ray method was determined the structure of potassium xanthates widely used under sulphide ore flotation of the composition: KS₂COR, where R-C_nH_2n+I, n=2,3,4,5.

The structure have layer character. Inside of the layers there are polyhedra connected with each other. Outside of the layers there are hydrofobe alkyl groups. In the nearest surrounding of the K⁺ ions there are S and O atoms forming three types of polyhedra: seven- and octahill. In the first case the polyhedron represents the monohatted trigonal prism in one of the basis of which there are S atoms. The O atom occupies the seventh summit. In the second case the coordination polyhedron represents the distorted quadriangle prism or antiprism in one of the basis of which there are S atoms of the two xanthates. In the opposite basis there are O and S atoms of the two other xanthate molecules. Monotyped prisms being bonded by the common basis form the infinite columns which are in its turn connected with each other by their S-S edges.

The potassium xanthate structure layers consist of monotyped polyhedra and only in the ethylxanthate it is observed the simultaneous presence of both types of polyhedron. The structure motive explaines the good cleavage. The interatomic distances and valent angles in all structures coincide.