Na6V4Mn2O15 is Pb (Zr_0.50 Ti_0.48) O_3-derived structured and crystallizes in the monoclinic P2/c space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. In the second Na site, Na(2) is bonded in a distorted hexagonal planar geometry to two equivalent O(1), two equivalent O(5), and two equivalent O(7) atoms. In the third Na site, Na(3) is bonded in a 1-coordinate geometry to one O(5), one O(7), one O(8), two equivalent O(3), and two equivalent O(4) atoms. In the fourth Na site, Na(4) is bonded in a 7-coordinate geometry to one O(2), one O(6), one O(8), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form VO4 tetrahedra that share corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-46°. In the second V site, V(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form VO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and  a cornercorner with one V(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-24°. Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form MnO6 octahedra that share corners with two equivalent V(2)O4 tetrahedra and corners with four equivalent V(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(3) is bonded to two equivalent Na(3), two equivalent Na(4), one V(1), and one Mn(1) atom to form distorted edge-sharing ONa4MnV octahedra. In the second O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Na(3), two equivalent Na(4), one V(1), and one Mn(1) atom. In the third O site, O(5) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one V(2), and one Mn(1) atom. In the fourth O site, O(6) is bonded in a distorted linear geometry to two equivalent Na(1), two equivalent Na(4), and two equivalent V(2) atoms. In the fifth O site, O(7) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one V(2), and one Mn(1) atom. In the sixth O site, O(8) is bonded in a 3-coordinate geometry to one Na(3), one Na(4), and one V(2) atom. In the seventh O site, O(1) is bonded in a 1-coordinate geometry to one Na(2), one V(1), and one Mn(1) atom. In the eighth O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(4), one V(1), and one Mn(1) atom.
Na6V4Mn2O15 is Pb (Zr_0.50 Ti_0.48) O_3-derived structured and crystallizes in the monoclinic P2/c space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. Both Na(1)-O(2) bond lengths are 2.41 Å. Both Na(1)-O(5) bond lengths are 2.74 Å. There is one shorter (2.76 Å) and one longer (3.02 Å) Na(1)-O(6) bond length. Both Na(1)-O(7) bond lengths are 2.86 Å. In the second Na site, Na(2) is bonded in a distorted hexagonal planar geometry to two equivalent O(1), two equivalent O(5), and two equivalent O(7) atoms. Both Na(2)-O(1) bond lengths are 2.61 Å. Both Na(2)-O(5) bond lengths are 2.51 Å. Both Na(2)-O(7) bond lengths are 2.59 Å. In the third Na site, Na(3) is bonded in a 1-coordinate geometry to one O(5), one O(7), one O(8), two equivalent O(3), and two equivalent O(4) atoms. The Na(3)-O(5) bond length is 2.89 Å. The Na(3)-O(7) bond length is 2.77 Å. The Na(3)-O(8) bond length is 2.20 Å. There is one shorter (2.61 Å) and one longer (2.75 Å) Na(3)-O(3) bond length. There is one shorter (2.86 Å) and one longer (2.92 Å) Na(3)-O(4) bond length. In the fourth Na site, Na(4) is bonded in a 7-coordinate geometry to one O(2), one O(6), one O(8), two equivalent O(3), and two equivalent O(4) atoms. The Na(4)-O(2) bond length is 2.64 Å. The Na(4)-O(6) bond length is 2.98 Å. The Na(4)-O(8) bond length is 2.86 Å. There is one shorter (2.51 Å) and one longer (2.82 Å) Na(4)-O(3) bond length. There is one shorter (2.63 Å) and one longer (2.97 Å) Na(4)-O(4) bond length. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form VO4 tetrahedra that share corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-46°. The V(1)-O(1) bond length is 1.72 Å. The V(1)-O(2) bond length is 1.76 Å. The V(1)-O(3) bond length is 1.77 Å. The V(1)-O(4) bond length is 1.75 Å. In the second V site, V(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form VO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and  a cornercorner with one V(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-24°. The V(2)-O(5) bond length is 1.73 Å. The V(2)-O(6) bond length is 1.81 Å. The V(2)-O(7) bond length is 1.72 Å. The V(2)-O(8) bond length is 1.69 Å. Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form MnO6 octahedra that share corners with two equivalent V(2)O4 tetrahedra and corners with four equivalent V(1)O4 tetrahedra. The Mn(1)-O(1) bond length is 2.26 Å. The Mn(1)-O(2) bond length is 2.32 Å. The Mn(1)-O(3) bond length is 2.19 Å. The Mn(1)-O(4) bond length is 2.11 Å. The Mn(1)-O(5) bond length is 2.14 Å. The Mn(1)-O(7) bond length is 2.11 Å. There are eight inequivalent O sites. In the first O site, O(3) is bonded to two equivalent Na(3), two equivalent Na(4), one V(1), and one Mn(1) atom to form distorted edge-sharing ONa4MnV octahedra. In the second O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Na(3), two equivalent Na(4), one V(1), and one Mn(1) atom. In the third O site, O(5) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one V(2), and one Mn(1) atom. In the fourth O site, O(6) is bonded in a distorted linear geometry to two equivalent Na(1), two equivalent Na(4), and two equivalent V(2) atoms. In the fifth O site, O(7) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one V(2), and one Mn(1) atom. In the sixth O site, O(8) is bonded in a 3-coordinate geometry to one Na(3), one Na(4), and one V(2) atom. In the seventh O site, O(1) is bonded in a 1-coordinate geometry to one Na(2), one V(1), and one Mn(1) atom. In the eighth O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(4), one V(1), and one Mn(1) atom.