DOE OSTI2020
K2LiNbO4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 2-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.61–3.11 Å. In the second K1+ site, K1+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.67–3.12 Å. In the third 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 2.68–3.29 Å. In the fourth K1+ site, K1+ is bonded to five O2- atoms to form distorted KO5 square pyramids that share corners with five NbO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.64–2.80 Å. In the fifth K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.57–3.08 Å. In the sixth K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.57–3.16 Å. In the seventh K1+ site, K1+ is bonded in a 2-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.58–3.05 Å. In the eighth K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.71–3.29 Å. There are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent NbO4 tetrahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one NbO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.01–2.04 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.99–2.46 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two NbO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.91–2.16 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two NbO4 tetrahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one NbO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.99–2.13 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with two equivalent KO5 square pyramids and an edgeedge with one LiO4 tetrahedra. There are a spread of Nb–O bond distances ranging from 1.87–1.90 Å. In the second Nb5+ site, Nb5+ is bonded to four O2- atoms to form NbO4 tetrahedra that share a cornercorner with one KO5 square pyramid and an edgeedge with one LiO4 tetrahedra. There are a spread of Nb–O bond distances ranging from 1.86–1.91 Å. In the third Nb5+ site, Nb5+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with two equivalent KO5 square pyramids and corners with two LiO4 tetrahedra. There are a spread of Nb–O bond distances ranging from 1.83–1.94 Å. In the fourth Nb5+ site, Nb5+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with four LiO4 tetrahedra and an edgeedge with one LiO4 tetrahedra. There are a spread of Nb–O bond distances ranging from 1.85–1.94 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four K1+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two K1+, two Li1+, and one Nb5+ atom. In the third O2- site, O2- is bonded to three K1+ and one Nb5+ atom to form distorted corner-sharing OK3Nb tetrahedra. In the fourth O2- site, O2- is bonded to four K1+ and one Nb5+ atom to form distorted corner-sharing OK4Nb trigonal bipyramids. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+ and one Nb5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two K1+, one Li1+, and one Nb5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four K1+, one Li1+, and one Nb5+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one Li1+, and one Nb5+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to three K1+, one Li1+, and one Nb5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to three K1+, two Li1+, and one Nb5+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Nb5+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to three K1+, one Li1+, and one Nb5+ atom. In the thirteenth O2- site, O2- is bonded in a 6-coordinate geometry to four K1+, one Li1+, and one Nb5+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to three K1+, two Li1+, and one Nb5+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two K1+, two Li1+, and one Nb5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, two Li1+, and one Nb5+ atom.