Na4Mn5O12 is Spinel-like structured and crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form NaO4 tetrahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, and corners with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-64°. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form NaO4 tetrahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, and corners with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-64°. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(5), and two equivalent O(6) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, and edges with three equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, and edges with three equivalent Mn(1)O6 octahedra. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), one Mn(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded to one Na(2), one Na(3), one Mn(1), and one Mn(2) atom to form distorted ONa2Mn2 trigonal pyramids that share corners with three equivalent O(3)NaMn3 tetrahedra, corners with three equivalent O(4)NaMn3 tetrahedra,  a cornercorner with one O(5)Na2Mn2 trigonal pyramid,  a cornercorner with one O(6)Na2Mn2 trigonal pyramid, corners with two equivalent O(2)Na2Mn2 trigonal pyramids,  an edgeedge with one O(5)Na2Mn2 trigonal pyramid, and  an edgeedge with one O(6)Na2Mn2 trigonal pyramid. In the third O site, O(3) is bonded to one Na(1), one Mn(2), and two equivalent Mn(1) atoms to form ONaMn3 tetrahedra that share  a cornercorner with one O(4)NaMn3 tetrahedra, corners with two equivalent O(6)Na2Mn2 trigonal pyramids, corners with three equivalent O(2)Na2Mn2 trigonal pyramids, corners with three equivalent O(5)Na2Mn2 trigonal pyramids,  an edgeedge with one O(3)NaMn3 tetrahedra, and edges with two equivalent O(4)NaMn3 tetrahedra. In the fourth O site, O(4) is bonded to one Na(1), one Mn(1), and two equivalent Mn(2) atoms to form ONaMn3 tetrahedra that share  a cornercorner with one O(3)NaMn3 tetrahedra, corners with two equivalent O(5)Na2Mn2 trigonal pyramids, corners with three equivalent O(2)Na2Mn2 trigonal pyramids, corners with three equivalent O(6)Na2Mn2 trigonal pyramids,  an edgeedge with one O(4)NaMn3 tetrahedra, and edges with two equivalent O(3)NaMn3 tetrahedra. In the fifth O site, O(5) is bonded to one Na(1), one Na(3), one Mn(1), and one Mn(3) atom to form distorted ONa2Mn2 trigonal pyramids that share corners with two equivalent O(4)NaMn3 tetrahedra, corners with three equivalent O(3)NaMn3 tetrahedra,  a cornercorner with one O(2)Na2Mn2 trigonal pyramid, corners with two equivalent O(5)Na2Mn2 trigonal pyramids, corners with three equivalent O(6)Na2Mn2 trigonal pyramids,  an edgeedge with one O(2)Na2Mn2 trigonal pyramid, and  an edgeedge with one O(6)Na2Mn2 trigonal pyramid. In the sixth O site, O(6) is bonded to one Na(1), one Na(3), one Mn(2), and one Mn(3) atom to form distorted ONa2Mn2 trigonal pyramids that share corners with two equivalent O(3)NaMn3 tetrahedra, corners with three equivalent O(4)NaMn3 tetrahedra,  a cornercorner with one O(2)Na2Mn2 trigonal pyramid, corners with two equivalent O(6)Na2Mn2 trigonal pyramids, corners with three equivalent O(5)Na2Mn2 trigonal pyramids,  an edgeedge with one O(2)Na2Mn2 trigonal pyramid, and  an edgeedge with one O(5)Na2Mn2 trigonal pyramid.
Na4Mn5O12 is Spinel-like structured and crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form NaO4 tetrahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, and corners with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-64°. The Na(1)-O(3) bond length is 2.18 Å. The Na(1)-O(4) bond length is 2.28 Å. The Na(1)-O(5) bond length is 2.18 Å. The Na(1)-O(6) bond length is 2.20 Å. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form NaO4 tetrahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, and corners with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-64°. Both Na(2)-O(1) bond lengths are 2.16 Å. Both Na(2)-O(2) bond lengths are 2.13 Å. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(5), and two equivalent O(6) atoms. Both Na(3)-O(2) bond lengths are 2.42 Å. Both Na(3)-O(5) bond lengths are 2.28 Å. Both Na(3)-O(6) bond lengths are 2.25 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, and edges with three equivalent Mn(2)O6 octahedra. The Mn(1)-O(1) bond length is 2.01 Å. The Mn(1)-O(2) bond length is 1.91 Å. The Mn(1)-O(4) bond length is 1.99 Å. The Mn(1)-O(5) bond length is 1.88 Å. Both Mn(1)-O(3) bond lengths are 1.99 Å. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, and edges with three equivalent Mn(1)O6 octahedra. The Mn(2)-O(1) bond length is 2.00 Å. The Mn(2)-O(2) bond length is 1.90 Å. The Mn(2)-O(3) bond length is 2.02 Å. The Mn(2)-O(6) bond length is 1.86 Å. There is one shorter (2.02 Å) and one longer (2.03 Å) Mn(2)-O(4) bond length. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with four equivalent Na(1)O4 tetrahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. Both Mn(3)-O(1) bond lengths are 2.00 Å. Both Mn(3)-O(5) bond lengths are 1.93 Å. Both Mn(3)-O(6) bond lengths are 1.93 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), one Mn(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded to one Na(2), one Na(3), one Mn(1), and one Mn(2) atom to form distorted ONa2Mn2 trigonal pyramids that share corners with three equivalent O(3)NaMn3 tetrahedra, corners with three equivalent O(4)NaMn3 tetrahedra,  a cornercorner with one O(5)Na2Mn2 trigonal pyramid,  a cornercorner with one O(6)Na2Mn2 trigonal pyramid, corners with two equivalent O(2)Na2Mn2 trigonal pyramids,  an edgeedge with one O(5)Na2Mn2 trigonal pyramid, and  an edgeedge with one O(6)Na2Mn2 trigonal pyramid. In the third O site, O(3) is bonded to one Na(1), one Mn(2), and two equivalent Mn(1) atoms to form ONaMn3 tetrahedra that share  a cornercorner with one O(4)NaMn3 tetrahedra, corners with two equivalent O(6)Na2Mn2 trigonal pyramids, corners with three equivalent O(2)Na2Mn2 trigonal pyramids, corners with three equivalent O(5)Na2Mn2 trigonal pyramids,  an edgeedge with one O(3)NaMn3 tetrahedra, and edges with two equivalent O(4)NaMn3 tetrahedra. In the fourth O site, O(4) is bonded to one Na(1), one Mn(1), and two equivalent Mn(2) atoms to form ONaMn3 tetrahedra that share  a cornercorner with one O(3)NaMn3 tetrahedra, corners with two equivalent O(5)Na2Mn2 trigonal pyramids, corners with three equivalent O(2)Na2Mn2 trigonal pyramids, corners with three equivalent O(6)Na2Mn2 trigonal pyramids,  an edgeedge with one O(4)NaMn3 tetrahedra, and edges with two equivalent O(3)NaMn3 tetrahedra. In the fifth O site, O(5) is bonded to one Na(1), one Na(3), one Mn(1), and one Mn(3) atom to form distorted ONa2Mn2 trigonal pyramids that share corners with two equivalent O(4)NaMn3 tetrahedra, corners with three equivalent O(3)NaMn3 tetrahedra,  a cornercorner with one O(2)Na2Mn2 trigonal pyramid, corners with two equivalent O(5)Na2Mn2 trigonal pyramids, corners with three equivalent O(6)Na2Mn2 trigonal pyramids,  an edgeedge with one O(2)Na2Mn2 trigonal pyramid, and  an edgeedge with one O(6)Na2Mn2 trigonal pyramid. In the sixth O site, O(6) is bonded to one Na(1), one Na(3), one Mn(2), and one Mn(3) atom to form distorted ONa2Mn2 trigonal pyramids that share corners with two equivalent O(3)NaMn3 tetrahedra, corners with three equivalent O(4)NaMn3 tetrahedra,  a cornercorner with one O(2)Na2Mn2 trigonal pyramid, corners with two equivalent O(6)Na2Mn2 trigonal pyramids, corners with three equivalent O(5)Na2Mn2 trigonal pyramids,  an edgeedge with one O(2)Na2Mn2 trigonal pyramid, and  an edgeedge with one O(5)Na2Mn2 trigonal pyramid.