Materials Data on Hf2Be17 by Materials Project
Be17Hf2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are four inequivalent Be sites. In the first Be site, Be is bonded in a 2-coordinate geometry to thirteen Be and one Hf atom. There are a spread of Be–Be bond distances ranging from 2.11–2.40 Å. The Be–Hf bond length is 2.64 Å. In the second Be site, Be is bonded to ten Be and two equivalent Hf atoms to form distorted BeHf2Be10 cuboctahedra that share corners with twenty-two BeHf2Be10 cuboctahedra, edges with ten BeHf3Be9 cuboctahedra, and faces with eighteen BeHf2Be10 cuboctahedra. There are four shorter (2.14 Å) and four longer (2.17 Å) Be–Be bond lengths. Both Be–Hf bond lengths are 2.85 Å. In the third Be site, Be is bonded to ten Be and two equivalent Hf atoms to form distorted BeHf2Be10 cuboctahedra that share corners with twenty-four BeHf2Be10 cuboctahedra, edges with five BeHf3Be9 cuboctahedra, and faces with twenty-one BeHf2Be10 cuboctahedra. There are a spread of Be–Be bond distances ranging from 2.16–2.34 Å. Both Be–Hf bond lengths are 2.67 Å. In the fourth Be site, Be is bonded to nine Be and three equivalent Hf atoms to form a mixture of corner, edge, and face-sharing BeHf3Be9 cuboctahedra. Both Be–Be bond lengths are 2.15 Å. There are a spread of Be–Hf bond distances ranging from 2.72–2.84 Å. Hf is bonded in a 10-coordinate geometry to nineteen Be atoms.