Materials Data on Ba2PrNb(CuO4)2 by Materials Project
PrBa2NbCu2O8 crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 12-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.86–2.95 Å. In the second Ba2+ site, Ba2+ is bonded in a 12-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.85–2.97 Å. Pr3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.52–2.54 Å. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four equivalent NbO6 octahedra and corners with two equivalent CuO5 square pyramids. The corner-sharing octahedra tilt angles range from 18–19°. There are two shorter (2.00 Å) and four longer (2.02 Å) Nb–O bond lengths. Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one NbO6 octahedra and corners with four equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.01 Å) and one longer (2.40 Å) Cu–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, two equivalent Pr3+, and two equivalent Cu2+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+, one Nb5+, and one Cu2+ atom. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, two equivalent Pr3+, and two equivalent Cu2+ atoms.