DOI: 10.17188/1666659
title: Materials Data on Ba4Na2W2O11 by Materials Project

description: Ba4Na2W2O11 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with four equivalent WO6 octahedra and corners with two equivalent WO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Na–O bond distances ranging from 2.26–2.42 Å. In the second Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 square pyramids that share corners with two equivalent WO6 octahedra and corners with three equivalent WO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 10°. There are a spread of Na–O bond distances ranging from 2.25–2.63 Å. There are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–3.23 Å. In the second Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–3.25 Å. There are two inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to five O2- atoms to form WO5 trigonal bipyramids that share corners with two equivalent NaO6 octahedra and corners with three equivalent NaO5 square pyramids. The corner-sharing octahedral tilt angles are 7°. There are a spread of W–O bond distances ranging from 1.85–1.94 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with four equivalent NaO6 octahedra and corners with two equivalent NaO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of W–O bond distances ranging from 1.94–1.99 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+, four Ba2+, and one W6+ atom to form distorted OBa4NaW octahedra that share corners with two equivalent OBa4NaW octahedra, corners with four OBa2NaW trigonal pyramids, and edges with two equivalent OBa4NaW octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded to one Na1+, four Ba2+, and one W6+ atom to form distorted OBa4NaW octahedra that share corners with two equivalent OBa4NaW octahedra, corners with four OBa2NaW trigonal pyramids, and edges with two equivalent OBa4NaW octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O2- site, O2- is bonded in a 6-coordinate geometry to one Na1+, four Ba2+, and one W6+ atom. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to one Na1+, four Ba2+, and one W6+ atom. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to one Na1+, four Ba2+, and one W6+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, four Ba2+, and one W6+ atom. In the seventh O2- site, O2- is bonded in a linear geometry to one Na1+, four Ba2+, and one W6+ atom. In the eighth O2- site, O2- is bonded to one Na1+, two equivalent Ba2+, and one W6+ atom to form distorted OBa2NaW trigonal pyramids that share corners with four OBa4NaW octahedra and corners with two equivalent OBa2NaW trigonal pyramids. The corner-sharing octahedra tilt angles range from 45–59°. In the ninth O2- site, O2- is bonded to one Na1+, two equivalent Ba2+, and one W6+ atom to form distorted OBa2NaW trigonal pyramids that share corners with four OBa4NaW octahedra and corners with two equivalent OBa2NaW trigonal pyramids. The corner-sharing octahedra tilt angles range from 45–59°.