Materials Data on CaB3H3O7 by Materials Project
CaB3O4(OH)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.85 Å. There are three inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.47–1.51 Å. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.53 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.36 Å) and two longer (1.38 Å) B–O bond length. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.66 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Ca2+ and two B3+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ca2+ and two B3+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Ca2+, one B3+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Ca2+, one B3+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two B3+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ca2+, one B3+, and one H1+ atom.