Materials Data on RbYMg6 by Materials Project
RbMg6Y is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Rb is bonded to ten Mg and two equivalent Y atoms to form distorted RbY2Mg10 cuboctahedra that share corners with four equivalent MgRb2Mg10 cuboctahedra, corners with six equivalent RbY2Mg10 cuboctahedra, edges with two equivalent MgRb2Mg10 cuboctahedra, edges with four equivalent YRb2Mg10 cuboctahedra, faces with two equivalent RbY2Mg10 cuboctahedra, faces with two equivalent YRb2Mg10 cuboctahedra, and faces with eight MgY2Mg10 cuboctahedra. There are a spread of Rb–Mg bond distances ranging from 3.37–3.53 Å. Both Rb–Y bond lengths are 3.62 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 11-coordinate geometry to two equivalent Rb, seven Mg, and two equivalent Y atoms. There are a spread of Mg–Mg bond distances ranging from 3.31–3.43 Å. There are one shorter (3.25 Å) and one longer (3.61 Å) Mg–Y bond lengths. In the second Mg site, Mg is bonded to ten Mg and two equivalent Y atoms to form MgY2Mg10 cuboctahedra that share corners with four equivalent YRb2Mg10 cuboctahedra, corners with six equivalent MgY2Mg10 cuboctahedra, edges with two equivalent YRb2Mg10 cuboctahedra, edges with four equivalent MgRb2Mg10 cuboctahedra, faces with two equivalent YRb2Mg10 cuboctahedra, faces with four MgY2Mg10 cuboctahedra, and faces with six equivalent RbY2Mg10 cuboctahedra. There are four shorter (3.41 Å) and two longer (3.44 Å) Mg–Mg bond lengths. Both Mg–Y bond lengths are 3.53 Å. In the third Mg site, Mg is bonded in a 11-coordinate geometry to two equivalent Rb, seven Mg, and two equivalent Y atoms. There are a spread of Mg–Mg bond distances ranging from 3.32–3.44 Å. Both Mg–Y bond lengths are 3.28 Å. In the fourth Mg site, Mg is bonded to two equivalent Rb and ten Mg atoms to form distorted MgRb2Mg10 cuboctahedra that share corners with four equivalent RbY2Mg10 cuboctahedra, corners with six equivalent MgRb2Mg10 cuboctahedra, edges with two equivalent RbY2Mg10 cuboctahedra, edges with four equivalent MgY2Mg10 cuboctahedra, faces with two equivalent RbY2Mg10 cuboctahedra, faces with four MgY2Mg10 cuboctahedra, and faces with six equivalent YRb2Mg10 cuboctahedra. Y is bonded to two equivalent Rb and ten Mg atoms to form YRb2Mg10 cuboctahedra that share corners with four equivalent MgY2Mg10 cuboctahedra, corners with six equivalent YRb2Mg10 cuboctahedra, edges with two equivalent MgY2Mg10 cuboctahedra, edges with four equivalent RbY2Mg10 cuboctahedra, faces with two equivalent RbY2Mg10 cuboctahedra, faces with two equivalent YRb2Mg10 cuboctahedra, and faces with eight MgY2Mg10 cuboctahedra.