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DOE OSTI · 1475913

Materials Data on K2Na2Nb(WO4)3 by Materials Project

Abstract

K2Na2Nb(WO4)3 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share corners with four equivalent KO12 cuboctahedra, corners with eight equivalent NaO12 cuboctahedra, faces with two equivalent NaO12 cuboctahedra, faces with four equivalent KO12 cuboctahedra, faces with two equivalent NbO6 octahedra, and faces with six WO6 octahedra. There are a spread of K–O bond distances ranging from 2.82–2.88 Å. Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with four equivalent NaO12 cuboctahedra, corners with eight equivalent KO12 cuboctahedra, faces with two equivalent KO12 cuboctahedra, faces with four equivalent NaO12 cuboctahedra, faces with two equivalent NbO6 octahedra, and faces with six WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.80–2.84 Å. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four WO6 octahedra, faces with four equivalent KO12 cuboctahedra, and faces with four equivalent NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Nb–O bond distances ranging from 1.99–2.04 Å. There are three inequivalent W5+ sites. In the first W5+ site, W5+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra, faces with four equivalent KO12 cuboctahedra, and faces with four equivalent NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of W–O bond distances ranging from 2.00–2.10 Å. In the second W5+ site, W5+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four WO6 octahedra, faces with four equivalent KO12 cuboctahedra, and faces with four equivalent NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of W–O bond distances ranging from 1.93–2.00 Å. In the third W5+ site, W5+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four WO6 octahedra, faces with four equivalent KO12 cuboctahedra, and faces with four equivalent NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of W–O bond distances ranging from 1.94–2.01 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent K1+, two equivalent Na1+, and two equivalent W5+ atoms to form distorted OK2Na2W2 octahedra that share corners with six OK2Na2W2 octahedra, edges with four OK2Na2W2 octahedra, and faces with eight OK4W2 octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the second O2- site, O2- is bonded to two equivalent K1+, two equivalent Na1+, and two equivalent W5+ atoms to form distorted OK2Na2W2 octahedra that share corners with eighteen OK2Na2W2 octahedra, edges with two equivalent OK2Na2W2 octahedra, and faces with four OK4W2 octahedra. The corner-sharing octahedra tilt angles range from 1–60°. In the third O2- site, O2- is bonded to two equivalent K1+, two equivalent Na1+, and two equivalent W5+ atoms to form distorted OK2Na2W2 octahedra that share corners with fourteen OK2Na2W2 octahedra, edges with two equivalent OK2Na2W2 octahedra, and faces with six OK4NbW octahedra. The corner-sharing octahedra tilt angles range from 1–59°. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent K1+, two equivalent Na1+, and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded to two equivalent K1+, two equivalent Na1+, and two W5+ atoms to form a mixture of distorted face, edge, and corner-sharing OK2Na2W2 octahedra. The corner-sharing octahedra tilt angles range from 1–62°. In the sixth O2- site, O2- is bonded in a distorted linear geometry to two equivalent K1+, two equivalent Na1+, one Nb5+, and one W5+ atom. In the seventh O2- site, O2- is bonded to four equivalent K1+ and two W5+ atoms to form distorted OK4W2 octahedra that share corners with fourteen OK2Na2W2 octahedra, edges with four OK4W2 octahedra, and faces with six OK2Na2W2 octahedra. The corner-sharing octahedra tilt angles range from 0–59°. In the eighth O2- site, O2- is bonded to four equivalent Na1+ and two W5+ atoms to form distorted ONa4W2 octahedra that share corners with ten OK2Na2W2 octahedra, edges with two equivalent ONa4W2 octahedra, and faces with six OK2Na2W2 octahedra. The corner-sharing octahedra tilt angles range from 0–59°. In the ninth O2- site, O2- is bonded to four equivalent K1+, one Nb5+, and one W5+ atom to form distorted OK4NbW octahedra that share corners with sixteen OK2Na2W2 octahedra, edges with four OK4W2 octahedra, and faces with four OK2Na2W2 octahedra. The corner-sharing octahedra tilt angles range from 1–62°. In the tenth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Na1+, one Nb5+, and one W5+ atom.

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2020-07-15. Materials Data on K2Na2Nb(WO4)3 by Materials Project. https://doi.org/10.17188/1475913

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