DOE OSTI2020
KNb4AsO13 crystallizes in the triclinic P1 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 2.72–3.13 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.76–3.37 Å. In the third 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 2.75–3.02 Å. In the fourth K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.37 Å. There are sixteen inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are a spread of Nb–O bond distances ranging from 1.87–2.16 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 20–41°. There are a spread of Nb–O bond distances ranging from 1.87–2.17 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 20–29°. There are a spread of Nb–O bond distances ranging from 1.83–2.29 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 20–29°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the seventh Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are a spread of Nb–O bond distances ranging from 1.87–2.17 Å. In the eighth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are a spread of Nb–O bond distances ranging from 1.87–2.17 Å. In the ninth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 20–40°. There are a spread of Nb–O bond distances ranging from 1.86–2.17 Å. In the tenth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are a spread of Nb–O bond distances ranging from 1.87–2.16 Å. In the eleventh Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the twelfth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the thirteenth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 20–28°. There are a spread of Nb–O bond distances ranging from 1.83–2.30 Å. In the fourteenth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with two AsO4 tetrahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the fifteenth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–40°. There are a spread of Nb–O bond distances ranging from 1.86–2.17 Å. In the sixteenth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 20–41°. There are a spread of Nb–O bond distances ranging from 1.87–2.17 Å. There are four inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There is two shorter (1.70 Å) and two longer (1.74 Å) As–O bond length. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There is two shorter (1.70 Å) and two longer (1.74 Å) As–O bond length. In the third As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There is two shorter (1.70 Å) and two longer (1.74 Å) As–O bond length. In the fourth As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There is two shorter (1.70 Å) and two longer (1.74 Å) As–O bond length. There are fifty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one As5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Nb5+, and one As5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Nb5+ atoms. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one As5+ atom. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Nb5+, and one As5+ atom. In the nineteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the twentieth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the twenty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the twenty-second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the twenty-third O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twenty-fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twenty-fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twenty-sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twenty-seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twenty-eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the twenty-ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the thirtieth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the thirty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the thirty-second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the thirty-third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the thirty-fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one As5+ atom. In the thirty-fifth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one As5+ atom. In the thirty-sixth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one As5+ atom. In the thirty-seventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the thirty-eighth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the thirty-ninth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the fortieth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the forty-first O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the forty-second O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the forty-third O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the forty-fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the forty-fifth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the forty-sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+ and two Nb5+ atoms. In the forty-seventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the forty-eighth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Nb5+ atoms. In the forty-ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two