DOE OSTI2020
KNbB2O6 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.92–3.41 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.90–3.47 Å. In the third K1+ site, K1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.84–3.50 Å. In the fourth 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 2.84–3.34 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 22–28°. There are a spread of Nb–O bond distances ranging from 1.81–2.32 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 4–20°. There are a spread of Nb–O bond distances ranging from 1.81–2.30 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 4–22°. There are a spread of Nb–O bond distances ranging from 1.81–2.31 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 20–28°. There are a spread of Nb–O bond distances ranging from 1.82–2.31 Å. There are eight inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.36–1.41 Å. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.36 Å) and one longer (1.41 Å) B–O bond length. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.36 Å) and one longer (1.41 Å) B–O bond length. In the fourth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.36–1.41 Å. In the fifth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.37 Å) and one longer (1.40 Å) B–O bond length. In the sixth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.36 Å) and one longer (1.41 Å) B–O bond length. In the seventh B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.36 Å) and one longer (1.41 Å) B–O bond length. In the eighth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.36 Å) and one longer (1.41 Å) B–O bond length. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Nb5+, and one B3+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two B3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one B3+ atom. 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+, one Nb5+, and one B3+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Nb5+, and one B3+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to two K1+ and two B3+ atoms. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Nb5+, and one B3+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Nb5+, and one B3+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Nb5+, and one B3+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Nb5+, and one B3+ atom. In the twelfth O2- site, O2- is bonded in a linear geometry to one K1+, one Nb5+, and one B3+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Nb5+, and one B3+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two B3+ atoms. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Nb5+, and one B3+ atom. In the sixteenth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Nb5+, and one B3+ atom. In the seventeenth O2- site, O2- is bonded in a distorted linear geometry to two Nb5+ atoms. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Nb5+, and one B3+ atom. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one B3+ atom. In the twentieth O2- site, O2- is bonded in a bent 120 degrees geometry to two K1+ and two B3+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Nb5+ atoms. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one B3+ atom. In the twenty-third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Nb5+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Nb5+, and one B3+ atom.