A new polymorph of Mo3S4 was synthesized at 13 GPa and 1450 °C from a stoichiometric mixture of elements. It crystallizes in a triclinic unit cell (space group P1 (No. 2)) with cell constants of a = 6.364(2) Ǻ, b = 6.608(2) Ǻ, c = 6.809(2) Ǻ, α = 103.899(3) °, β = 117.753(3) °, γ = 103.958(3) °, and V = 224.25(13) Ǻ(3). The structure of Mo3S4 is composed of edge- and face-sharing MoS6 octahedra. It was closely related to the structure of MMo2S4 type compounds (M = V, Cr, Fe, and Co). Mo3S4 can be regarded as a derivative with M = Mo. The calculated density of 6.160 g/cm(3) was much larger than 5.191 g/cm(3) of famous polymorphic Mo6S8 (Chevrel phase). Mo3S4 was metallic and did not show any superconducting transition down to 2 K. The bond-valence sums suggested that Mo3S4 can be classified in the class III-B of mixed-valence compounds; all Mo ions have a similar nonintegral valence. Electronic structure calculations revealed that the conduction band of Mo3S4 contains much contribution of the relatively narrow Mo 4d bands as well as the bands composed of hybridized Mo4d-S3d orbitals.

A new polymorph of Mo3S4 is synthesized from a mixture of Mo and S in the molar ratio of 3:4 (h-BN cell, 13 GPa, 1450°C) and characterized by single crystal XRD, electrical resistivity measurements, and LAPW electronic band structure calculations. It crystallizes in the triclinic space group P1 with Z = 2. The structure is composed of edgeand face-sharing MoS6 octahedra. Mo3S4 is metallic and does not show any superconducting transition down to 2 K. -(FUKUOKA*, H.; MASUOKA, K.; HANAOKA, T.; INUMARU, K.; Inorg. Chem. 52 (2013) 14, 7918-7922, http://dx.doi.org/10.1021/ic400423n ; Dep. Appl. Chem., Fac. Eng., Hiroshima Univ., Higashi-Hiroshima 739, Japan; Eng.) -W. Pewestorf 38-021