Materials Data on Y2O3 by Materials Project

Y2O3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.25–2.59 Å. In the second Y3+ site, Y3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing YO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Y–O bond distances ranging from 2.21–2.48 Å. In the third Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.26–2.75 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to five Y3+ atoms to form distorted OY5 square pyramids that share corners with seven OY4 tetrahedra, corners with two equivalent OY4 trigonal pyramids, edges with two equivalent OY6 octahedra, edges with two equivalent OY5 square pyramids, edges with three OY4 tetrahedra, and edges with three equivalent OY4 trigonal pyramids. In the second O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share a cornercorner with one OY6 octahedra, corners with five equivalent OY5 square pyramids, corners with four OY4 tetrahedra, corners with three equivalent OY4 trigonal pyramids, edges with two equivalent OY6 octahedra, an edgeedge with one OY5 square pyramid, and edges with two equivalent OY4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. In the third O2- site, O2- is bonded to four Y3+ atoms to form distorted OY4 trigonal pyramids that share a cornercorner with one OY6 octahedra, corners with two equivalent OY5 square pyramids, corners with nine OY4 tetrahedra, corners with two equivalent OY4 trigonal pyramids, edges with three equivalent OY5 square pyramids, and edges with two equivalent OY4 trigonal pyramids. The corner-sharing octahedral tilt angles are 37°. In the fourth O2- site, O2- is bonded to four Y3+ atoms to form distorted OY4 tetrahedra that share corners with two equivalent OY6 octahedra, corners with two equivalent OY5 square pyramids, corners with four OY4 tetrahedra, corners with six equivalent OY4 trigonal pyramids, an edgeedge with one OY6 octahedra, edges with two equivalent OY5 square pyramids, and an edgeedge with one OY4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the fifth O2- site, O2- is bonded to six Y3+ atoms to form OY6 octahedra that share corners with six OY4 tetrahedra, corners with two equivalent OY4 trigonal pyramids, edges with two equivalent OY6 octahedra, edges with four equivalent OY5 square pyramids, and edges with six OY4 tetrahedra.

三氧化二钇（Y₂O₃）以单斜晶系C2/m空间群结晶，其结构为三维网状。体系中存在3个不等价的Y³+位点。
在第一个Y³+位点中，Y³+采取7配位几何构型，与7个O²-原子配位，Y-O键长分布范围为2.25~2.59 Å。
在第二个Y³+位点中，Y³+与6个O²-原子配位，形成共边与共顶角混合型的YO₆八面体，共顶角八面体倾斜角为0°，Y-O键长分布范围为2.21~2.48 Å。
在第三个Y³+位点中，Y³+采取7配位几何构型，与7个O²-原子配位，Y-O键长分布范围为2.26~2.75 Å。
体系中同时存在5个不等价的O²-位点。
在第一个O²-位点中，O²-与5个Y³+原子配位，形成畸变的OY₅四方锥结构；该四方锥分别与7个OY₄四面体共顶角、2个等价OY₄三角锥共顶角、2个等价OY₆八面体共边、2个等价OY₅四方锥共边、3个OY₄四面体共边以及3个等价OY₄三角锥共边。
在第二个O²-位点中，O²-与4个Y³+原子配位，形成OY₄四面体结构；该四面体分别与1个OY₆八面体共顶角、5个等价OY₅四方锥共顶角、4个OY₄四面体共顶角、3个等价OY₄三角锥共顶角、2个等价OY₆八面体共边、1个OY₅四方锥共边以及2个等价OY₄四面体共边，共顶角八面体倾斜角为49°。
在第三个O²-位点中，O²-与4个Y³+原子配位，形成畸变的OY₄三角锥结构；该三角锥分别与1个OY₆八面体共顶角、2个等价OY₅四方锥共顶角、9个OY₄四面体共顶角、2个等价OY₄三角锥共顶角、3个等价OY₅四方锥共边以及2个等价OY₄三角锥共边，共顶角八面体倾斜角为37°。
在第四个O²-位点中，O²-与4个Y³+原子配位，形成畸变的OY₄四面体结构；该四面体分别与2个等价OY₆八面体共顶角、2个等价OY₅四方锥共顶角、4个OY₄四面体共顶角、6个等价OY₄三角锥共顶角、1个OY₆八面体共边、2个等价OY₅四方锥共边以及1个OY₄四面体共边，共顶角八面体倾斜角为13°。
在第五个O²-位点中，O²-与6个Y³+原子配位，形成OY₆八面体结构；该八面体分别与6个OY₄四面体共顶角、2个等价OY₄三角锥共顶角、2个等价OY₆八面体共边、4个等价OY₅四方锥共边以及6个OY₄四面体共边。