Materials Data on Er2Ge2S7 by Materials Project

Er2Ge2S7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to seven S2- atoms to form distorted ErS7 pentagonal bipyramids that share a cornercorner with one GeS6 octahedra, corners with four ErS7 pentagonal bipyramids, corners with two equivalent GeS4 tetrahedra, an edgeedge with one GeS6 octahedra, edges with two equivalent ErS7 pentagonal bipyramids, an edgeedge with one GeS4 tetrahedra, and a faceface with one GeS6 octahedra. The corner-sharing octahedral tilt angles are 23°. There are a spread of Er–S bond distances ranging from 2.67–2.93 Å. In the second Er3+ site, Er3+ is bonded to seven S2- atoms to form distorted ErS7 pentagonal bipyramids that share a cornercorner with one GeS6 octahedra, corners with four ErS7 pentagonal bipyramids, corners with two equivalent GeS4 tetrahedra, an edgeedge with one GeS6 octahedra, edges with two equivalent ErS7 pentagonal bipyramids, an edgeedge with one GeS4 tetrahedra, and a faceface with one GeS6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are a spread of Er–S bond distances ranging from 2.67–3.07 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to six S2- atoms to form distorted GeS6 octahedra that share corners with two ErS7 pentagonal bipyramids, edges with two ErS7 pentagonal bipyramids, faces with two equivalent GeS6 octahedra, and faces with two ErS7 pentagonal bipyramids. There are a spread of Ge–S bond distances ranging from 2.31–2.81 Å. In the second Ge4+ site, Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share corners with four ErS7 pentagonal bipyramids and edges with two ErS7 pentagonal bipyramids. There are a spread of Ge–S bond distances ranging from 2.20–2.28 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Er3+ and two equivalent Ge4+ atoms. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Er3+ and two equivalent Ge4+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to two Er3+ and two equivalent Ge4+ atoms. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Er3+ and one Ge4+ atom. In the fifth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Er3+ and one Ge4+ atom. In the sixth S2- site, S2- is bonded in an L-shaped geometry to one Er3+ and one Ge4+ atom. In the seventh S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to two Er3+ and one Ge4+ atom.Er₂Ge₂S₇结晶于单斜晶系P2₁空间群。该晶体结构为三维结构，存在两个不等价的Er³+位点。在第一个Er³+位点中，Er³+与7个S²-离子配位，形成畸变的ErS₇五角双锥配位多面体，该多面体与1个GeS₆八面体共享1个角顶、与4个ErS₇五角双锥共享角顶、与2个等价的GeS₄四面体共享角顶，与1个GeS₆八面体共享1条棱、与2个等价的ErS₇五角双锥共享棱、与1个GeS₄四面体共享1条棱，同时与1个GeS₆八面体共面。八面体共顶倾斜角为23°。Er–S键的键长分布范围为2.67~2.93 Å。在第二个Er³+位点中，Er³+同样与7个S²-离子配位，形成畸变的ErS₇五角双锥配位多面体，该多面体与1个GeS₆八面体共享1个角顶、与4个ErS₇五角双锥共享角顶、与2个等价的GeS₄四面体共享角顶，与1个GeS₆八面体共享1条棱、与2个等价的ErS₇五角双锥共享棱、与1个GeS₄四面体共享1条棱，同时与1个GeS₆八面体共面。八面体共顶倾斜角为14°。Er–S键的键长分布范围为2.67~3.07 Å。体系中存在两个不等价的Ge⁴+位点。在第一个Ge⁴+位点中，Ge⁴+与6个S²-离子配位，形成畸变的GeS₆八面体配位多面体，该多面体与2个ErS₇五角双锥共享角顶、与2个ErS₇五角双锥共享棱、与2个等价的GeS₆八面体共面、与2个ErS₇五角双锥共面。Ge–S键的键长分布范围为2.31~2.81 Å。在第二个Ge⁴+位点中，Ge⁴+与4个S²-离子配位，形成GeS₄四面体配位多面体，该多面体与4个ErS₇五角双锥共享角顶、与2个ErS₇五角双锥共享棱。Ge–S键的键长分布范围为2.20~2.28 Å。体系中存在7个不等价的S²-位点。在第一个S²-位点中，S²-以畸变矩形跷跷板型配位几何与2个Er³+以及2个等价的Ge⁴+离子成键。在第二个S²-位点中，S²-以畸变矩形跷跷板型配位几何与2个Er³+以及2个等价的Ge⁴+离子成键。在第三个S²-位点中，S²-以四配位几何与2个Er³+以及2个等价的Ge⁴+离子成键。在第四个S²-位点中，S²-以三配位几何与2个等价的Er³+以及1个Ge⁴+离子成键。在第五个S²-位点中，S²-以畸变矩形跷跷板型配位几何与3个Er³+以及1个Ge⁴+离子成键。在第六个S²-位点中，S²-以L型配位几何与1个Er³+以及1个Ge⁴+离子成键。在第七个S²-位点中，S²-以畸变三角非共面配位几何与2个Er³+以及1个Ge⁴+离子成键。