Materials Data on Tb2SeOF2 by Materials Project
Tb2SeOF2 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are two inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded in a 4-coordinate geometry to four equivalent Se2-, three equivalent O2-, and one F1- atom. There are two shorter (3.05 Å) and two longer (3.06 Å) Tb–Se bond lengths. There are one shorter (2.27 Å) and two longer (2.29 Å) Tb–O bond lengths. The Tb–F bond length is 2.44 Å. In the second Tb3+ site, Tb3+ is bonded in a 7-coordinate geometry to two equivalent Se2-, one O2-, and six F1- atoms. Both Tb–Se bond lengths are 3.07 Å. The Tb–O bond length is 2.28 Å. There are a spread of Tb–F bond distances ranging from 2.37–2.44 Å. Se2- is bonded in a 6-coordinate geometry to six Tb3+ atoms. O2- is bonded to four Tb3+ atoms to form distorted OTb4 tetrahedra that share corners with two equivalent OTb4 tetrahedra, corners with two equivalent FTb4 tetrahedra, edges with two equivalent OTb4 tetrahedra, and edges with two equivalent FTb4 tetrahedra. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal non-coplanar geometry to three equivalent Tb3+ atoms. In the second F1- site, F1- is bonded to four Tb3+ atoms to form distorted FTb4 tetrahedra that share corners with two equivalent OTb4 tetrahedra, corners with six equivalent FTb4 tetrahedra, and edges with two equivalent OTb4 tetrahedra.