Materials Data on CaMg6Zr by Materials Project

Abstract

CaMg6Zr crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ca is bonded to twelve Mg atoms to form CaMg12 cuboctahedra that share corners with four equivalent CaMg12 cuboctahedra, corners with eight equivalent ZrMg12 cuboctahedra, edges with twenty-four MgCa2Mg8Zr2 cuboctahedra, faces with two equivalent CaMg12 cuboctahedra, faces with four equivalent ZrMg12 cuboctahedra, and faces with twelve MgCa2Mg8Zr2 cuboctahedra. There are four shorter (3.24 Å) and eight longer (3.36 Å) Ca–Mg bond lengths. There are three inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Zr atoms to form distorted MgCa2Mg8Zr2 cuboctahedra that share corners with twelve equivalent MgCa2Mg8Zr2 cuboctahedra, edges with four equivalent CaMg12 cuboctahedra, edges with four equivalent ZrMg12 cuboctahedra, edges with sixteen MgCa2Mg8Zr2 cuboctahedra, faces with two equivalent CaMg12 cuboctahedra, faces with two equivalent ZrMg12 cuboctahedra, and faces with fourteen MgCa2Mg8Zr2 cuboctahedra. All Mg–Mg bond lengths are 3.27 Å. Both Mg–Zr bond lengths are 3.24 Å. In the second Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Zr atoms to form distorted MgCa2Mg8Zr2 cuboctahedra that share corners with twelve equivalent MgCa2Mg8Zr2 cuboctahedra, edges with four equivalent CaMg12 cuboctahedra, edges with four equivalent ZrMg12 cuboctahedra, edges with sixteen MgCa2Mg8Zr2 cuboctahedra, faces with two equivalent CaMg12 cuboctahedra, faces with two equivalent ZrMg12 cuboctahedra, and faces with fourteen MgCa2Mg8Zr2 cuboctahedra. There are two shorter (3.05 Å) and two longer (3.42 Å) Mg–Mg bond lengths. Both Mg–Zr bond lengths are 3.17 Å. In the third Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Zr atoms to form distorted MgCa2Mg8Zr2 cuboctahedra that share corners with twelve equivalent MgCa2Mg8Zr2 cuboctahedra, edges with four equivalent CaMg12 cuboctahedra, edges with four equivalent ZrMg12 cuboctahedra, edges with sixteen MgCa2Mg8Zr2 cuboctahedra, faces with two equivalent CaMg12 cuboctahedra, faces with two equivalent ZrMg12 cuboctahedra, and faces with fourteen MgCa2Mg8Zr2 cuboctahedra. Both Mg–Zr bond lengths are 3.18 Å. Zr is bonded to twelve Mg atoms to form ZrMg12 cuboctahedra that share corners with four equivalent ZrMg12 cuboctahedra, corners with eight equivalent CaMg12 cuboctahedra, edges with twenty-four MgCa2Mg8Zr2 cuboctahedra, faces with two equivalent ZrMg12 cuboctahedra, faces with four equivalent CaMg12 cuboctahedra, and faces with twelve MgCa2Mg8Zr2 cuboctahedra.