Materials Data on Sm2SiO5 by Materials Project

Abstract

Sm2SiO5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Sm3+ sites. In the first Sm3+ site, Sm3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sm–O bond distances ranging from 2.34–2.80 Å. In the second Sm3+ site, Sm3+ is bonded to seven O2- atoms to form distorted SmO7 hexagonal pyramids that share corners with two equivalent SiO4 tetrahedra, edges with six equivalent SmO7 hexagonal pyramids, and an edgeedge with one SiO4 tetrahedra. There are a spread of Sm–O bond distances ranging from 2.33–2.59 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent SmO7 hexagonal pyramids and an edgeedge with one SmO7 hexagonal pyramid. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Sm3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Sm3+ and one Si4+ atom. In the third O2- site, O2- is bonded to four Sm3+ atoms to form a mixture of edge and corner-sharing OSm4 tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Sm3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent Sm3+ and one Si4+ atom.