NaMn2O4 is Spinel structured and crystallizes in the orthorhombic Imma space group. Na(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form NaO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-67°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted MnO6 octahedra that share corners with six equivalent Na(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Na(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing ONaMn3 tetrahedra. In the second O site, O(2) is bonded to one Na(1), one Mn(1), and two equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing ONaMn3 trigonal pyramids.
NaMn2O4 is Spinel structured and crystallizes in the orthorhombic Imma space group. Na(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form NaO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-67°. Both Na(1)-O(1) bond lengths are 2.18 Å. Both Na(1)-O(2) bond lengths are 2.17 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted MnO6 octahedra that share corners with six equivalent Na(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. Both Mn(1)-O(2) bond lengths are 2.26 Å. All Mn(1)-O(1) bond lengths are 2.00 Å. In the second Mn site, Mn(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Na(1)O4 tetrahedra, edges with two equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Both Mn(2)-O(1) bond lengths are 1.99 Å. All Mn(2)-O(2) bond lengths are 1.95 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing ONaMn3 tetrahedra. In the second O site, O(2) is bonded to one Na(1), one Mn(1), and two equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing ONaMn3 trigonal pyramids.