Materials Data on KTa5Pb2O15 by Materials Project
Pb2KTa5O15 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.87–2.99 Å. There are five inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent PbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–36°. There are a spread of Ta–O bond distances ranging from 1.94–2.05 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent PbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–30°. There are a spread of Ta–O bond distances ranging from 1.96–2.10 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent PbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–35°. There are a spread of Ta–O bond distances ranging from 1.95–2.10 Å. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent PbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–39°. There are a spread of Ta–O bond distances ranging from 1.94–2.05 Å. In the fifth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 14–39°. There are a spread of Ta–O bond distances ranging from 1.92–2.08 Å. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to twelve O2- atoms to form PbO12 cuboctahedra that share faces with two equivalent PbO12 cuboctahedra and faces with eight TaO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.67–2.91 Å. In the second Pb2+ site, Pb2+ is bonded in a 3-coordinate geometry to eight O2- atoms. There are a spread of Pb–O bond distances ranging from 2.48–3.17 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ta5+ and two equivalent Pb2+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta5+ atoms. 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 4-coordinate geometry to two Ta5+ and two equivalent Pb2+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ta5+ and one Pb2+ atom. In the sixth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ta5+ and one Pb2+ atom. In the seventh O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ta5+ and one Pb2+ atom. In the eighth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ and two Pb2+ atoms. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ and two equivalent Pb2+ atoms. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta5+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ta5+ and one Pb2+ atom. In the twelfth O2- site, O2- is bonded in a linear geometry to two Ta5+ and two equivalent Pb2+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted linear geometry to two Ta5+ and two equivalent Pb2+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted linear geometry to two Ta5+ and two equivalent Pb2+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted linear geometry to two Ta5+ and two equivalent Pb2+ atoms.