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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Ho5Si3B by Materials Project

Ho5BSi3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded in a 7-coordinate geometry to two equivalent B3- and five equivalent Si4- atoms. Both Ho–B bond lengths are 2.58 Å. There are a spread of Ho–Si bond distances ranging from 2.96–3.43 Å. In the second Ho3+ site, Ho3+ is bonded to six equivalent Si4- atoms to form a mixture of distorted corner, edge, and face-sharing HoSi6 octahedra. The corner-sharing octahedral tilt angles are 33°. All Ho–Si bond lengths are 3.04 Å. B3- is bonded to six equivalent Ho3+ atoms to form face-sharing BHo6 octahedra. Si4- is bonded in a 9-coordinate geometry to nine Ho3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho5(SiB4)2 by Materials Project

Ho5Si2B8 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 12-coordinate geometry to nine B and three equivalent Si atoms. There are a spread of Ho–B bond distances ranging from 2.62–2.95 Å. There are one shorter (3.04 Å) and two longer (3.11 Å) Ho–Si bond lengths. In the second Ho site, Ho is bonded to two equivalent B and four equivalent Si atoms to form corner-sharing HoSi4B2 octahedra. The corner-sharing octahedral tilt angles are 57°. Both Ho–B bond lengths are 2.71 Å. All Ho–Si bond lengths are 2.89 Å. There are three inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to four equivalent Ho and five B atoms. There are a spread of B–B bond distances ranging from 1.75–1.83 Å. In the second B site, B is bonded in a 3-coordinate geometry to six equivalent Ho and three B atoms. The B–B bond length is 1.83 Å. In the third B site, B is bonded in a 9-coordinate geometry to five Ho and four equivalent B atoms. Si is bonded in a 9-coordinate geometry to eight Ho and one Si atom. The Si–Si bond length is 2.35 Å.

36 MATERIALS SCIENCE↗