Materials Data on Y2Mg by Materials Project

Abstract

MgY2 is beta-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to four Mg and eight Y atoms to form distorted MgY8Mg4 cuboctahedra that share corners with six equivalent YY8Mg4 cuboctahedra, corners with twelve MgY8Mg4 cuboctahedra, edges with three equivalent MgY8Mg4 cuboctahedra, edges with fifteen YY9Mg3 cuboctahedra, faces with five MgY8Mg4 cuboctahedra, and faces with fifteen YY9Mg3 cuboctahedra. There are two shorter (3.36 Å) and two longer (3.52 Å) Mg–Mg bond lengths. There are a spread of Mg–Y bond distances ranging from 3.34–3.65 Å. In the second Mg site, Mg is bonded to four Mg and eight Y atoms to form distorted MgY8Mg4 cuboctahedra that share corners with six equivalent YY8Mg4 cuboctahedra, corners with twelve MgY8Mg4 cuboctahedra, edges with three equivalent MgY8Mg4 cuboctahedra, edges with fifteen YY9Mg3 cuboctahedra, faces with five MgY8Mg4 cuboctahedra, and faces with fifteen YY9Mg3 cuboctahedra. Both Mg–Mg bond lengths are 3.52 Å. There are a spread of Mg–Y bond distances ranging from 3.39–3.79 Å. There are four inequivalent Y sites. In the first Y site, Y is bonded to three Mg and nine Y atoms to form YY9Mg3 cuboctahedra that share corners with eighteen YY9Mg3 cuboctahedra, edges with eight YY7Mg5 cuboctahedra, edges with ten MgY8Mg4 cuboctahedra, faces with seven MgY8Mg4 cuboctahedra, and faces with thirteen YY9Mg3 cuboctahedra. There are a spread of Y–Y bond distances ranging from 3.43–3.53 Å. In the second Y site, Y is bonded to five Mg and seven Y atoms to form YY7Mg5 cuboctahedra that share corners with eighteen YY9Mg3 cuboctahedra, edges with eight MgY8Mg4 cuboctahedra, edges with ten YY9Mg3 cuboctahedra, faces with eight MgY8Mg4 cuboctahedra, and faces with twelve YY9Mg3 cuboctahedra. There are a spread of Y–Y bond distances ranging from 3.46–3.52 Å. In the third Y site, Y is bonded to four Mg and eight Y atoms to form YY8Mg4 cuboctahedra that share corners with eighteen YY9Mg3 cuboctahedra, edges with six MgY8Mg4 cuboctahedra, edges with twelve YY9Mg3 cuboctahedra, faces with nine MgY8Mg4 cuboctahedra, and faces with eleven YY9Mg3 cuboctahedra. There are two shorter (3.52 Å) and two longer (3.56 Å) Y–Y bond lengths. In the fourth Y site, Y is bonded to four Mg and eight Y atoms to form YY8Mg4 cuboctahedra that share corners with six equivalent YY8Mg4 cuboctahedra, corners with twelve MgY8Mg4 cuboctahedra, edges with six MgY8Mg4 cuboctahedra, edges with twelve YY9Mg3 cuboctahedra, faces with six MgY8Mg4 cuboctahedra, and faces with fourteen YY9Mg3 cuboctahedra. Both Y–Y bond lengths are 3.52 Å.