Materials Data on BaMg6Zr by Materials Project

Abstract

BaMg6Zr crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ba is bonded to twelve Mg atoms to form BaMg12 cuboctahedra that share corners with four equivalent BaMg12 cuboctahedra, corners with eight equivalent ZrMg12 cuboctahedra, edges with eight equivalent MgBa2Mg8Zr2 cuboctahedra, faces with two equivalent BaMg12 cuboctahedra, faces with four equivalent MgBa2Mg8Zr2 cuboctahedra, and faces with four equivalent ZrMg12 cuboctahedra. There are a spread of Ba–Mg bond distances ranging from 3.38–3.58 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Ba, eight Mg, and two equivalent Zr atoms to form distorted MgBa2Mg8Zr2 cuboctahedra that share corners with twelve equivalent MgBa2Mg8Zr2 cuboctahedra, edges with four equivalent BaMg12 cuboctahedra, edges with four equivalent ZrMg12 cuboctahedra, faces with two equivalent BaMg12 cuboctahedra, faces with two equivalent ZrMg12 cuboctahedra, and faces with six equivalent MgBa2Mg8Zr2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.34–3.39 Å. There are one shorter (3.37 Å) and one longer (3.39 Å) Mg–Zr bond lengths. In the second Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba, six Mg, and two equivalent Zr atoms. There are one shorter (3.00 Å) and one longer (3.02 Å) Mg–Mg bond lengths. Both Mg–Zr bond lengths are 3.16 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba, six Mg, and two equivalent Zr atoms. Both Mg–Zr bond lengths are 3.20 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba, six Mg, and two equivalent Zr atoms. 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 BaMg12 cuboctahedra, edges with eight equivalent MgBa2Mg8Zr2 cuboctahedra, faces with two equivalent ZrMg12 cuboctahedra, faces with four equivalent BaMg12 cuboctahedra, and faces with four equivalent MgBa2Mg8Zr2 cuboctahedra.