Materials Data on K6Ta11O30 by Materials Project
K6Ta11O30 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.88–3.08 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to thirteen O2- atoms. There are a spread of K–O bond distances ranging from 2.95–3.38 Å. In the third K1+ site, K1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.75 Å) and two longer (2.97 Å) K–O bond lengths. In the fourth K1+ site, K1+ is bonded to twelve O2- atoms to form distorted KO12 cuboctahedra that share faces with two equivalent KO12 cuboctahedra and faces with eight TaO6 octahedra. There are a spread of K–O bond distances ranging from 2.71–3.27 Å. There are seven inequivalent Ta+4.91+ sites. In the first Ta+4.91+ site, Ta+4.91+ is bonded to six O2- atoms to form distorted TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–27°. There are a spread of Ta–O bond distances ranging from 1.85–2.15 Å. In the second Ta+4.91+ site, Ta+4.91+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–39°. There are a spread of Ta–O bond distances ranging from 1.94–2.10 Å. In the third Ta+4.91+ site, Ta+4.91+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–35°. There are a spread of Ta–O bond distances ranging from 1.94–2.19 Å. In the fourth Ta+4.91+ site, Ta+4.91+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and faces with two equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–35°. There are a spread of Ta–O bond distances ranging from 1.86–2.22 Å. In the fifth Ta+4.91+ site, Ta+4.91+ is bonded to six O2- atoms to form distorted corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 10–39°. There are a spread of Ta–O bond distances ranging from 1.84–2.16 Å. In the sixth Ta+4.91+ site, Ta+4.91+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 6–32°. There are a spread of Ta–O bond distances ranging from 1.95–2.07 Å. In the seventh Ta+4.91+ site, Ta+4.91+ is bonded in a 3-coordinate geometry to nine O2- atoms. There are a spread of Ta–O bond distances ranging from 2.02–2.60 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and four Ta+4.91+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two equivalent Ta+4.91+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ta+4.91+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two K1+ and two equivalent Ta+4.91+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to four Ta+4.91+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the eleventh O2- site, O2- is bonded in a distorted linear geometry to four K1+ and two Ta+4.91+ atoms. In the twelfth O2- site, O2- is bonded in a distorted linear geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Ta+4.91+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+ and three Ta+4.91+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted linear geometry to two K1+ and two equivalent Ta+4.91+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted linear geometry to one K1+ and two equivalent Ta+4.91+ atoms. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two equivalent Ta+4.91+ atoms.