Materials Data on Er2Si2PbO8 by Materials Project
Er2PbSi2O8 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to six O2- atoms to form ErO6 pentagonal pyramids that share corners with four equivalent ErO6 pentagonal pyramids, corners with four SiO4 tetrahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Er–O bond distances ranging from 2.10–2.42 Å. In the second Er3+ site, Er3+ is bonded to six O2- atoms to form distorted ErO6 pentagonal pyramids that share corners with four equivalent ErO6 pentagonal pyramids, corners with four SiO4 tetrahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Er–O bond distances ranging from 2.07–2.42 Å. There are three inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.39 Å) and three longer (2.99 Å) Pb–O bond lengths. In the second Pb2+ site, Pb2+ is bonded in a 6-coordinate geometry to nine O2- atoms. There are a spread of Pb–O bond distances ranging from 2.47–3.09 Å. In the third Pb2+ site, Pb2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.47 Å) and three longer (2.80 Å) Pb–O bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four ErO6 pentagonal pyramids and an edgeedge with one ErO6 pentagonal pyramid. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four ErO6 pentagonal pyramids and an edgeedge with one ErO6 pentagonal pyramid. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Er3+, two Pb2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Er3+, one Pb2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Er3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Er3+, one Pb2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Er3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Er3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Er3+, one Pb2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Er3+, two Pb2+, and one Si4+ atom.