Materials Data on Sr2TmCu2(BiO4)2 by Materials Project
Sr2TmCu2(BiO4)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.67–2.79 Å. Tm3+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Tm–O bond lengths are 2.37 Å. Cu+1.50+ is bonded to five O2- atoms to form distorted CuO5 square pyramids that share a cornercorner with one BiO6 octahedra and corners with four equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.89 Å) and one longer (2.50 Å) Cu–O bond lengths. Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share corners with four equivalent BiO6 octahedra, a cornercorner with one CuO5 square pyramid, and edges with eight equivalent BiO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Bi–O bond distances ranging from 2.14–2.78 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Sr2+, two equivalent Tm3+, and two equivalent Cu+1.50+ atoms. In the second O2- site, O2- is bonded to one Sr2+ and five equivalent Bi3+ atoms to form a mixture of edge and corner-sharing OSrBi5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the third O2- site, O2- is bonded to four equivalent Sr2+, one Cu+1.50+, and one Bi3+ atom to form a mixture of distorted edge and corner-sharing OSr4CuBi octahedra. The corner-sharing octahedra tilt angles range from 0–25°.