Materials Data on Tm2SeO2 by Materials Project
Tm2SeO2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Tm3+ is bonded in a 4-coordinate geometry to three equivalent Se2- and four equivalent O2- atoms. All Tm–Se bond lengths are 2.94 Å. All Tm–O bond lengths are 2.25 Å. Se2- is bonded to six equivalent Tm3+ atoms to form distorted SeTm6 octahedra that share corners with twelve equivalent OTm4 tetrahedra, edges with six equivalent SeTm6 octahedra, and edges with six equivalent OTm4 tetrahedra. O2- is bonded to four equivalent Tm3+ atoms to form OTm4 tetrahedra that share corners with six equivalent SeTm6 octahedra, corners with six equivalent OTm4 tetrahedra, edges with three equivalent SeTm6 octahedra, and edges with three equivalent OTm4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–48°.