Materials Data on Sm2Si2O7 by Materials Project
Sm2Si2O7 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 7-coordinate geometry to seven O2- atoms. There are a spread of Sm–O bond distances ranging from 2.37–2.61 Å. In the second Sm3+ site, Sm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sm–O bond distances ranging from 2.32–2.65 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.68 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sm3+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Sm3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Sm3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Sm3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Sm3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Sm3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Sm3+ and one Si4+ atom.