Cu2MnTi3S8 and Cu2NiTi3S8 compounds were prepared by high-temperature synthesis. The crystal structure of these quaternary phases was investigated by X-ray powder diffraction. The compounds are described in the thiospinel structure (space group Fd (3) over barm) with the lattice constants a = 1.00353(1) nm (Cu2MnTi3S8) and a = 0.99716(1) mn (Cu2NiTi3S8). The atomic parameters were calculated in anisotropic approximation (R-1 = 0.0456 and R-1 = 0.0520 for Cu2MnTi3S8 and Cu2NiTi3S8, respectively). (C) 2006 Elsevier Ltd. All rights reserved.