Materials Data on Eu2MgH6 by Materials Project
Eu2MgH6 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Mg2+ is bonded to six H1- atoms to form MgH6 octahedra that share corners with six equivalent EuH12 cuboctahedra and faces with six equivalent EuH12 cuboctahedra. There are four shorter (2.02 Å) and two longer (2.03 Å) Mg–H bond lengths. Eu2+ is bonded to twelve H1- atoms to form EuH12 cuboctahedra that share corners with six equivalent EuH12 cuboctahedra, corners with three equivalent MgH6 octahedra, faces with eight equivalent EuH12 cuboctahedra, and faces with three equivalent MgH6 octahedra. The corner-sharing octahedra tilt angles range from 24–25°. There are a spread of Eu–H bond distances ranging from 2.58–2.86 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded in a 1-coordinate geometry to one Mg2+ and four equivalent Eu2+ atoms. In the second H1- site, H1- is bonded in a 1-coordinate geometry to one Mg2+ and four equivalent Eu2+ atoms.