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DOE OSTI · 1663063

Materials Data on Na2CeO3 by Materials Project

Abstract

Na2CeO3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with three NaO6 octahedra, corners with three CeO6 octahedra, edges with four CeO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 9–14°. There are a spread of Na–O bond distances ranging from 2.43–2.74 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two NaO6 octahedra, corners with four CeO6 octahedra, edges with four CeO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 4–15°. There are a spread of Na–O bond distances ranging from 2.44–2.75 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six NaO6 octahedra, edges with six NaO6 octahedra, and edges with six CeO6 octahedra. The corner-sharing octahedra tilt angles range from 12–15°. There are a spread of Na–O bond distances ranging from 2.46–2.55 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share a cornercorner with one NaO6 octahedra, corners with five CeO6 octahedra, edges with four CeO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 9–12°. There are a spread of Na–O bond distances ranging from 2.41–2.65 Å. In the fifth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two NaO6 octahedra, corners with four CeO6 octahedra, edges with four CeO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 8–13°. There are a spread of Na–O bond distances ranging from 2.45–2.70 Å. In the sixth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six NaO6 octahedra, edges with five CeO6 octahedra, and edges with seven NaO6 octahedra. The corner-sharing octahedra tilt angles range from 10–14°. There are a spread of Na–O bond distances ranging from 2.44–2.63 Å. In the seventh Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with four CeO6 octahedra, edges with four CeO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 9–10°. There are a spread of Na–O bond distances ranging from 2.39–2.72 Å. There are four inequivalent Ce4+ sites. In the first Ce4+ site, Ce4+ is bonded to six O2- atoms to form CeO6 octahedra that share corners with six NaO6 octahedra, edges with four CeO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 9–11°. There are a spread of Ce–O bond distances ranging from 2.23–2.40 Å. In the second Ce4+ site, Ce4+ is bonded to six O2- atoms to form CeO6 octahedra that share corners with six NaO6 octahedra, edges with three CeO6 octahedra, and edges with nine NaO6 octahedra. The corner-sharing octahedra tilt angles range from 4–13°. There are a spread of Ce–O bond distances ranging from 2.12–2.38 Å. In the third Ce4+ site, Ce4+ is bonded to six O2- atoms to form CeO6 octahedra that share corners with six NaO6 octahedra, edges with three CeO6 octahedra, and edges with nine NaO6 octahedra. The corner-sharing octahedra tilt angles range from 9–10°. There are two shorter (2.26 Å) and four longer (2.28 Å) Ce–O bond lengths. In the fourth Ce4+ site, Ce4+ is bonded to six O2- atoms to form CeO6 octahedra that share corners with six NaO6 octahedra, edges with three CeO6 octahedra, and edges with nine NaO6 octahedra. The corner-sharing octahedra tilt angles range from 7–11°. There are two shorter (2.25 Å) and four longer (2.29 Å) Ce–O bond lengths. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to five Na1+ and one Ce4+ atom to form a mixture of corner and edge-sharing ONa5Ce octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the second O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form ONa4Ce2 octahedra that share corners with six ONa4Ce2 octahedra and edges with twelve ONa5Ce octahedra. The corner-sharing octahedra tilt angles range from 2–12°. In the third O2- site, O2- is bonded to three Na1+ and three Ce4+ atoms to form ONa3Ce3 octahedra that share corners with six ONa4Ce2 octahedra and edges with twelve ONa5Ce octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the fourth O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form a mixture of corner and edge-sharing ONa4Ce2 octahedra. The corner-sharing octahedra tilt angles range from 2–10°. In the fifth O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form a mixture of distorted corner and edge-sharing ONa4Ce2 octahedra. The corner-sharing octahedra tilt angles range from 2–12°. In the sixth O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form distorted ONa4Ce2 octahedra that share corners with six ONa5Ce octahedra and edges with twelve ONa4Ce2 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the seventh O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form ONa4Ce2 octahedra that share corners with six ONa4Ce2 octahedra and edges with twelve ONa5Ce octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the eighth O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form a mixture of corner and edge-sharing ONa4Ce2 octahedra. The corner-sharing octahedra tilt angles range from 3–10°. In the ninth O2- site, O2- is bonded to four Na1+ and two Ce4+ atoms to form a mixture of distorted corner and edge-sharing ONa4Ce2 octahedra. The corner-sharing octahedra tilt angles range from 0–9°.

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2020-04-29. Materials Data on Na2CeO3 by Materials Project. https://doi.org/10.17188/1663063

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