Materials Data on La2Si2O7 by Materials Project
La2Si2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.39–2.94 Å. In the second La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.43–2.84 Å. In the third La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.37–2.99 Å. In the fourth La3+ site, La3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of La–O bond distances ranging from 2.41–2.75 Å. There are four 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 1.62–1.69 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 1.61–1.68 Å. In the third 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 1.61–1.67 Å. In the fourth 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 fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three La3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one La3+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two La3+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two La3+ and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one La3+ and two Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one La3+ and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom.