Étude structurale de combinaisons sulfurées et séléniées du molybdène: I. Structure cristalline de Mo3Se4

The crystals of Mo₃Se₄, are rhombohedral, space group $\text{R}\text{3}$, with two formula units in a cell: a = 6 658 Å, α = 91.58°.The structure was solved by the heavy atom method and refined by a full-matrix least-squares program to R = 0.045 for 537 independent reflexions. The structure consists of selenium chains parallel to the three axes such as those of metallic selenium, with wide channels running in the three directions. A few channels are occupied by “Mo₆” clusters so that Mo₃Se₄ can be regarded as a metallic compound.