Materials Data on HoNiB4 by Materials Project
HoNiB4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded in a 4-coordinate geometry to sixteen B+1.50- atoms. There are a spread of Ho–B bond distances ranging from 2.77–2.86 Å. In the second Ho3+ site, Ho3+ is bonded in a 8-coordinate geometry to sixteen B+1.50- atoms. There are eight shorter (2.79 Å) and eight longer (2.84 Å) Ho–B bond lengths. Ni3+ is bonded in a 6-coordinate geometry to six B+1.50- atoms. There are two shorter (2.07 Å) and four longer (2.18 Å) Ni–B bond lengths. There are two inequivalent B+1.50- sites. In the first B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four Ho3+, one Ni3+, and four B+1.50- atoms. There are a spread of B–B bond distances ranging from 1.68–1.75 Å. In the second B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four Ho3+, two equivalent Ni3+, and three B+1.50- atoms. The B–B bond length is 1.69 Å.