Materials Data on BaAl2Sb2O7 by Materials Project
BaAl2Sb2O7 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Ba2+ is bonded to six equivalent O2- atoms to form distorted BaO6 pentagonal pyramids that share corners with six equivalent AlO4 tetrahedra. All Ba–O bond lengths are 2.82 Å. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three equivalent BaO6 pentagonal pyramids and a cornercorner with one AlO4 tetrahedra. There is one shorter (1.73 Å) and three longer (1.79 Å) Al–O bond length. Sb3+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. All Sb–O bond lengths are 1.98 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ba2+, one Al3+, and one Sb3+ atom. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Al3+ atoms.