Thallium(I) copper(I) thorium(IV) tris­elenide, TlCuThSe₃

Thallium(I) copper(I) thorium(IV) tris­elenide, TlCuThSe₃, crystallizes with four formula units in the space group Cmcm in the KCuZrS₃ structure type. There is one crystallographic­ally independent Th, Tl, and Cu atom at a site of symmetry 2/m.., m2m, and m2m, respectively. There are two crystallographically independent Se atoms at sites of symmetry m.. and m2m. The structure consists of sheets of edge-sharing ThSe₆ octa­hedra and CuSe₄ tetra­hedra stacked parallel to the (010) face, separated by layers filled with chains of Tl running parallel to [100]. Each Tl is coordinated by a trigonal prism of Se atoms.

Caesium diuranium hexa­telluride

Single crystals of CsU₂Te₆ were synthesized from the reaction of U, Te, and Cs₂Te₃ at 1273 K. CsU₂Te₆ crystallizes in the space group Cmcm in the CsTh₂Te₆ structure type. The asymmetric unit comprises one U (site symmetry m2m), one Cs (m2m; half-occupancy) and two Te atoms (m.. and m2m). The structure of CsU₂Te₆ consists of infinite [U₂Te₆] layers perpendicular to [010] separated by Cs atoms. There are infinite Te-Te-Te linear chains along [001].