Materials Data on NaMg6W by Materials Project

Abstract

NaMg6W crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Na is bonded to twelve Mg atoms to form NaMg12 cuboctahedra that share corners with four equivalent NaMg12 cuboctahedra, corners with eight equivalent WMg12 cuboctahedra, edges with eight equivalent MgNa2Mg8W2 cuboctahedra, faces with two equivalent NaMg12 cuboctahedra, faces with four equivalent MgNa2Mg8W2 cuboctahedra, and faces with four equivalent WMg12 cuboctahedra. There are a spread of Na–Mg bond distances ranging from 3.10–3.26 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent W atoms to form distorted MgNa2Mg8W2 cuboctahedra that share corners with twelve equivalent MgNa2Mg8W2 cuboctahedra, edges with four equivalent NaMg12 cuboctahedra, edges with four equivalent WMg12 cuboctahedra, faces with two equivalent NaMg12 cuboctahedra, faces with two equivalent WMg12 cuboctahedra, and faces with six equivalent MgNa2Mg8W2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.09–3.13 Å. There are one shorter (3.10 Å) and one longer (3.12 Å) Mg–W bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Na, eight Mg, and two equivalent W atoms. There are a spread of Mg–Mg bond distances ranging from 2.85–3.37 Å. Both Mg–W bond lengths are 2.97 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Na, eight Mg, and two equivalent W atoms. Both Mg–W bond lengths are 2.98 Å. In the fourth Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Na, eight Mg, and two equivalent W atoms. Both Mg–W bond lengths are 3.00 Å. W is bonded to twelve Mg atoms to form WMg12 cuboctahedra that share corners with four equivalent WMg12 cuboctahedra, corners with eight equivalent NaMg12 cuboctahedra, edges with eight equivalent MgNa2Mg8W2 cuboctahedra, faces with two equivalent WMg12 cuboctahedra, faces with four equivalent NaMg12 cuboctahedra, and faces with four equivalent MgNa2Mg8W2 cuboctahedra.