Materials Data on NaMnO2 by Materials Project

Abstract

NaMnO2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with four equivalent NaO6 octahedra, corners with six MnO5 square pyramids, edges with two equivalent NaO6 octahedra, edges with two equivalent MnO5 square pyramids, and faces with two MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 45–49°. There are a spread of Na–O bond distances ranging from 2.31–2.50 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with three equivalent NaO6 octahedra, corners with four equivalent MnO6 octahedra, corners with four MnO5 square pyramids, edges with three NaO6 octahedra, and faces with two equivalent MnO6 octahedra. The corner-sharing octahedra tilt angles range from 39–48°. There are a spread of Na–O bond distances ranging from 2.36–2.51 Å. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.26–2.61 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent MnO6 octahedra, corners with seven NaO6 octahedra, corners with four MnO5 square pyramids, edges with three NaO6 octahedra, edges with two equivalent MnO5 square pyramids, a faceface with one MnO6 octahedra, and a faceface with one MnO5 square pyramid. The corner-sharing octahedra tilt angles range from 39–49°. There are a spread of Na–O bond distances ranging from 2.35–2.49 Å. There are four inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to five O2- atoms to form MnO5 square pyramids that share corners with two equivalent MnO6 octahedra, corners with four NaO6 octahedra, corners with two equivalent MnO5 square pyramids, edges with two equivalent MnO5 square pyramids, and a faceface with one NaO6 octahedra. The corner-sharing octahedra tilt angles range from 41–79°. There are a spread of Mn–O bond distances ranging from 1.93–2.41 Å. In the second Mn3+ site, Mn3+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with two equivalent MnO6 octahedra, corners with six NaO6 octahedra, corners with four equivalent MnO5 square pyramids, edges with two equivalent NaO6 octahedra, edges with two equivalent MnO5 square pyramids, and a faceface with one NaO6 octahedra. The corner-sharing octahedra tilt angles range from 49–86°. There are a spread of Mn–O bond distances ranging from 1.92–2.58 Å. In the third Mn3+ site, Mn3+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share corners with six NaO6 octahedra, corners with four MnO5 square pyramids, edges with two equivalent MnO6 octahedra, and faces with three NaO6 octahedra. The corner-sharing octahedra tilt angles range from 45–48°. There are a spread of Mn–O bond distances ranging from 1.97–2.63 Å. In the fourth Mn3+ site, Mn3+ is bonded to five O2- atoms to form MnO5 square pyramids that share corners with four NaO6 octahedra, corners with six MnO5 square pyramids, edges with two equivalent NaO6 octahedra, edges with two equivalent MnO5 square pyramids, and a faceface with one NaO6 octahedra. The corner-sharing octahedra tilt angles range from 48–84°. There are four shorter (1.96 Å) and one longer (2.47 Å) Mn–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two equivalent Mn3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and three Mn3+ atoms. In the third O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two equivalent Mn3+ atoms. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to three Na1+ and three Mn3+ atoms. In the fifth O2- site, O2- is bonded to two Na1+ and three Mn3+ atoms to form distorted corner-sharing ONa2Mn3 trigonal bipyramids. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to three Na1+ and three Mn3+ atoms. In the seventh O2- site, O2- is bonded in a 6-coordinate geometry to three Na1+ and three Mn3+ atoms. In the eighth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two equivalent Mn3+ atoms.