Materials Data on KTa3CuO9 by Materials Project
KCuTa3O9 crystallizes in the orthorhombic Pnc2 space group. The structure is three-dimensional. K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.08 Å. There are three inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 31–41°. There are a spread of Ta–O bond distances ranging from 1.94–2.04 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 27–41°. There are a spread of Ta–O bond distances ranging from 1.95–2.06 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 27–41°. There are a spread of Ta–O bond distances ranging from 1.94–2.08 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (1.98 Å) and two longer (2.11 Å) Cu–O bond lengths. In the second Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. All Cu–O bond lengths are 1.98 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ta5+ and one Cu2+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ta5+ and one Cu2+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta5+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Ta5+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two equivalent Ta5+ atoms. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ta5+ and one Cu2+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two equivalent Ta5+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Ta5+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Ta5+ atoms.