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Materials Data on Yb4Mg3H14 by Materials Project

Yb4Mg3H14 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Mg2+ is bonded in a 7-coordinate geometry to seven H1- atoms. There are a spread of Mg–H bond distances ranging from 1.83–2.37 Å. There are two inequivalent Yb2+ sites. In the first Yb2+ site, Yb2+ is bonded in a 9-coordinate geometry to nine H1- atoms. There are a spread of Yb–H bond distances ranging from 2.27–2.39 Å. In the second Yb2+ site, Yb2+ is bonded in a 9-coordinate geometry to nine H1- atoms. There are three shorter (2.32 Å) and six longer (2.44 Å) Yb–H bond lengths. There are four inequivalent H1- sites. In the first H1- site, H1- is bonded to one Mg2+ and three Yb2+ atoms to form distorted HYb3Mg tetrahedra that share corners with fourteen HYb4 tetrahedra, corners with two equivalent HYb2Mg3 trigonal bipyramids, edges with four HYb4 tetrahedra, and edges with two equivalent HYb2Mg3 trigonal bipyramids. In the second H1- site, H1- is bonded to four Yb2+ atoms to form HYb4 tetrahedra that share corners with ten HYb4 tetrahedra, corners with six equivalent HYb2Mg3 trigonal bipyramids, and edges with eight HYb4 tetrahedra. In the third H1- site, H1- is bonded to three equivalent Mg2+ and two equivalent Yb2+ atoms to form distorted HYb2Mg3 trigonal bipyramids that share corners with ten HYb4 tetrahedra, corners with four equivalent HYb2Mg3 trigonal bipyramids, edges with four equivalent HYb3Mg tetrahedra, and faces with two equivalent HYb2Mg3 trigonal bipyramids. In the fourth H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Mg2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Yb19(Mg4H27)2 by Materials Project

Yb19Mg8H54 crystallizes in the cubic Im-3 space group. The structure is three-dimensional. Mg is bonded to six H atoms to form MgH6 octahedra that share corners with three equivalent MgH6 octahedra and a faceface with one YbH12 cuboctahedra. The corner-sharing octahedral tilt angles are 36°. There is three shorter (1.94 Å) and three longer (1.99 Å) Mg–H bond length. There are three inequivalent Yb sites. In the first Yb site, Yb is bonded in a 8-coordinate geometry to eight H atoms. There are a spread of Yb–H bond distances ranging from 2.23–2.45 Å. In the second Yb site, Yb is bonded in a distorted q6 geometry to ten H atoms. There are a spread of Yb–H bond distances ranging from 2.32–2.46 Å. In the third Yb site, Yb is bonded to twelve equivalent H atoms to form YbH12 cuboctahedra that share faces with eight equivalent MgH6 octahedra. All Yb–H bond lengths are 2.44 Å. There are four inequivalent H sites. In the first H site, H is bonded in a distorted see-saw-like geometry to four Yb atoms. In the second H site, H is bonded to four Yb atoms to form a mixture of edge and corner-sharing HYb4 tetrahedra. In the third H site, H is bonded to one Mg and three Yb atoms to form distorted HYb3Mg tetrahedra that share corners with sixteen HYb4 tetrahedra and edges with four HYb3Mg tetrahedra. In the fourth H site, H is bonded to two equivalent Mg and two Yb atoms to form distorted HYb2Mg2 tetrahedra that share corners with fourteen HYb4 tetrahedra and edges with seven HYb2Mg2 tetrahedra.

36 MATERIALS SCIENCE↗