Materials Data on Nb8S8O45 by Materials Project
(Nb2S2O11)8O2 crystallizes in the trigonal R-3 space group. The structure is three-dimensional and consists of three water molecules and one Nb2S2O11 framework. In the Nb2S2O11 framework, there are two inequivalent Nb sites. In the first Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with three NbO6 octahedra and corners with three SO4 tetrahedra. The corner-sharing octahedral tilt angles are 8°. There are a spread of Nb–O bond distances ranging from 1.88–2.14 Å. In the second Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with three equivalent NbO6 octahedra and corners with three equivalent SO4 tetrahedra. The corner-sharing octahedral tilt angles are 8°. There are three shorter (1.93 Å) and three longer (2.09 Å) Nb–O bond lengths. There are two inequivalent S sites. In the first S site, S is bonded to four O atoms to form SO4 tetrahedra that share corners with three NbO6 octahedra. The corner-sharing octahedra tilt angles range from 25–36°. There are a spread of S–O bond distances ranging from 1.42–1.52 Å. In the second S site, S is bonded to four O atoms to form SO4 tetrahedra that share corners with three equivalent NbO6 octahedra. The corner-sharing octahedral tilt angles are 32°. There is one shorter (1.42 Å) and three longer (1.51 Å) S–O bond length. There are eight inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Nb and one S atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Nb and one S atom. In the third O site, O is bonded in a single-bond geometry to one S atom. In the fourth O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Nb and one S atom. In the sixth O site, O is bonded in a linear geometry to two Nb atoms. In the seventh O site, O is bonded in a single-bond geometry to one S atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Nb and one S atom.