Na3MnO3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted NaO4 trigonal pyramids that share corners with four equivalent Mn(1)O4 tetrahedra and edges with two equivalent Na(2)O4 trigonal pyramids. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. Mn(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form MnO4 tetrahedra that share corners with two equivalent Mn(1)O4 tetrahedra and corners with four equivalent Na(2)O4 trigonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Mn(1) atom to form a mixture of distorted corner and edge-sharing ONa5Mn octahedra. The corner-sharing octahedral tilt angles are 37°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Na(3), and one Mn(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Na(1), two equivalent Na(3), and two equivalent Mn(1) atoms.
Na3MnO3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(3) atoms. The Na(1)-O(2) bond length is 2.45 Å. There is one shorter (2.29 Å) and one longer (2.31 Å) Na(1)-O(1) bond length. There is one shorter (2.51 Å) and one longer (2.62 Å) Na(1)-O(3) bond length. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted NaO4 trigonal pyramids that share corners with four equivalent Mn(1)O4 tetrahedra and edges with two equivalent Na(2)O4 trigonal pyramids. There is one shorter (2.35 Å) and one longer (2.37 Å) Na(2)-O(1) bond length. There is one shorter (2.30 Å) and one longer (2.38 Å) Na(2)-O(2) bond length. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. The Na(3)-O(1) bond length is 2.47 Å. There is one shorter (2.43 Å) and one longer (2.59 Å) Na(3)-O(2) bond length. There is one shorter (2.45 Å) and one longer (2.61 Å) Na(3)-O(3) bond length. Mn(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form MnO4 tetrahedra that share corners with two equivalent Mn(1)O4 tetrahedra and corners with four equivalent Na(2)O4 trigonal pyramids. The Mn(1)-O(1) bond length is 1.88 Å. The Mn(1)-O(2) bond length is 1.90 Å. There is one shorter (1.91 Å) and one longer (2.04 Å) Mn(1)-O(3) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Mn(1) atom to form a mixture of distorted corner and edge-sharing ONa5Mn octahedra. The corner-sharing octahedral tilt angles are 37°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Na(3), and one Mn(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Na(1), two equivalent Na(3), and two equivalent Mn(1) atoms.