Materials Data on NaMn2O4 by Materials Project

Abstract

NaMn2O4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are four shorter (2.42 Å) and two longer (2.47 Å) Na–O bond lengths. There are two inequivalent Mn+3.50+ sites. In the first Mn+3.50+ site, Mn+3.50+ is bonded to six O2- atoms to form edge-sharing MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.93–1.98 Å. In the second Mn+3.50+ site, Mn+3.50+ is bonded to six O2- atoms to form edge-sharing MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.94–2.24 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+ and three Mn+3.50+ atoms to form distorted ONaMn3 trigonal pyramids that share corners with four equivalent ONa2Mn3 square pyramids, corners with six equivalent ONaMn3 trigonal pyramids, edges with four equivalent ONa2Mn3 square pyramids, and an edgeedge with one ONaMn3 trigonal pyramid. In the second O2- site, O2- is bonded to two equivalent Na1+ and three Mn+3.50+ atoms to form distorted ONa2Mn3 square pyramids that share corners with five equivalent ONa2Mn3 square pyramids, corners with four equivalent ONaMn3 trigonal pyramids, edges with four equivalent ONa2Mn3 square pyramids, and edges with four equivalent ONaMn3 trigonal pyramids.