Materials Data on Sm2Se3O20 by Materials Project
Sm2Se3O20 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two Sm2Se3O20 sheets oriented in the (0, 1, 0) direction. Sm is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Sm–O bond distances ranging from 2.34–2.60 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a tetrahedral geometry to four O atoms. There is two shorter (1.67 Å) and two longer (1.71 Å) Se–O bond length. In the second Se site, Se is bonded in a tetrahedral geometry to four O atoms. There is one shorter (1.66 Å) and three longer (1.68 Å) Se–O bond length. There are ten inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Sm and one Se atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Sm and one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In the fourth O site, O is bonded in a single-bond geometry to one Sm atom. In the fifth O site, O is bonded in a single-bond geometry to one Sm atom. In the sixth O site, O is bonded in a single-bond geometry to one Se atom. In the seventh O site, O is bonded in a distorted single-bond geometry to one Sm atom. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one Sm and one Se atom. In the ninth O site, O is bonded in a single-bond geometry to one Sm atom. In the tenth O site, O is bonded in a bent 120 degrees geometry to one Sm and one Se atom.