Materials Data on TmBO3 by Materials Project
TmBO3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Tm–O bond lengths are 2.43 Å. In the second Tm3+ site, Tm3+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Tm–O bond lengths are 2.24 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.35 Å) and two longer (1.40 Å) B–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Tm3+ and one B3+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one B3+ atom.