Crystal structure of Mn 3Si 2Te 6

Abstract

The synthesis, magnetic, and electrical properties of a new silicon manganese telluride, semiconducting and ferrimagnetic, has been previously reported. The X-ray determination of the crystal structure of this compound was achieved by means of direct methods and three-dimensional Fourier syntheses. The final least-squares R w factor of the refinement is R w = 0.035. According to this study the chemical formula is Mn 3Si 2Te 6 with Z = 2, the trigonal unit cell is a = 7.029(2), c = 14.255(3) Å, the space group is P 31c . The crystal structure can be described as one of a layer-type compound. Along the c-axis direction, we observe a fully occupied layer of Mn or Si pairs octahedra, then a partially occupied layer of ordered Mn octahedra, and so on. The surroundings of Si atoms are similar to the one found in Si 2Te 3, and the fully occupied layer of octahedra may be compared to the one found in Fe 2P 2Se 6.