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Materials Data on KNa2(PO3)3 by Materials Project

KNa2(PO3)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. K1+ is bonded in a 5-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.74–3.48 Å. There are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.38–2.57 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.42–2.60 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–54°. There are a spread of P–O bond distances ranging from 1.49–1.64 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of P–O bond distances ranging from 1.49–1.65 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–57°. There is two shorter (1.50 Å) and two longer (1.64 Å) P–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two Na1+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent K1+ and two P5+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one K1+ and two P5+ atoms. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one K1+ and two P5+ atoms. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two equivalent Na1+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two Na1+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+, one Na1+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Na1+, and one P5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on KNa2 by Materials Project

KNa2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. K is bonded in a 12-coordinate geometry to four equivalent K and twelve Na atoms. There are three shorter (4.56 Å) and one longer (4.58 Å) K–K bond lengths. There are nine shorter (4.37 Å) and three longer (4.38 Å) K–Na bond lengths. There are two inequivalent Na sites. In the first Na site, Na is bonded to six equivalent K and six equivalent Na atoms to form a mixture of corner, edge, and face-sharing NaK6Na6 cuboctahedra. All Na–Na bond lengths are 3.74 Å. In the second Na site, Na is bonded to six equivalent K and six Na atoms to form a mixture of corner, edge, and face-sharing NaK6Na6 cuboctahedra. There are two shorter (3.71 Å) and two longer (3.73 Å) Na–Na bond lengths.

36 MATERIALS SCIENCE↗