Na2MnP2O7 crystallizes in the triclinic P1 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to one O(10), one O(17), one O(20), and one O(23) atom. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(10), one O(23), one O(4), and one O(6) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(18), one O(21), one O(26), one O(27), one O(3), and one O(7) atom. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(12), one O(13), one O(18), one O(21), and one O(25) atom. In the fifth Na site, Na(5) is bonded to one O(13), one O(20), one O(23), one O(24), one O(28), and one O(6) atom to form distorted NaO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, corners with two equivalent P(6)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and  an edgeedge with one Mn(4)O6 octahedra. In the sixth Na site, Na(6) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(14), one O(20), one O(26), and one O(6) atom. In the seventh Na site, Na(7) is bonded in a 5-coordinate geometry to one O(16), one O(19), one O(2), one O(27), and one O(5) atom. In the eighth Na site, Na(8) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(14), one O(15), one O(16), and one O(5) atom. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(16), one O(24), one O(27), one O(28), one O(5), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, corners with two equivalent P(8)O4 tetrahedra, and  an edgeedge with one Na(5)O6 octahedra. The corner-sharing octahedral tilt angles are 65°. In the second Mn site, Mn(2) is bonded to one O(10), one O(18), one O(26), one O(4), one O(7), and one O(9) atom to form distorted MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(14), one O(19), one O(2), and one O(25) atom to form MnO6 octahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. In the fourth Mn site, Mn(4) is bonded to one O(13), one O(17), one O(21), one O(23), one O(25), and one O(3) atom to form MnO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra,  an edgeedge with one Na(5)O6 octahedra, and  an edgeedge with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-52°. In the second P site, P(2) is bonded to one O(10), one O(11), one O(8), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one P(4)O4 tetrahedra, and  an edgeedge with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. In the third P site, P(3) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-47°. In the fourth P site, P(4) is bonded to one O(12), one O(13), one O(14), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-56°. In the fifth P site, P(5) is bonded to one O(15), one O(19), one O(20), and one O(21) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-69°. In the sixth P site, P(6) is bonded to one O(22), one O(23), one O(24), and one O(25) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, corners with two equivalent Na(5)O6 octahedra,  a cornercorner with one P(8)O4 tetrahedra, and  an edgeedge with one Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. In the seventh P site, P(7) is bonded to one O(15), one O(16), one O(17), and one O(18) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, and  a cornercorner with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-45°. In the eighth P site, P(8) is bonded to one O(22), one O(26), one O(27), and one O(28) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, and  a cornercorner with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-61°. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Na(8), one P(1), and one P(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(7), one Mn(3), and one P(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(3), one Mn(4), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Na(2), one Mn(2), and one P(3) atom. In the fifth O site, O(5) is bonded in a 1-coordinate geometry to one Na(7), one Na(8), one Mn(1), and one P(1) atom. In the sixth O site, O(6) is bonded to one Na(2), one Na(5), one Na(6), and one P(1) atom to form distorted ONa3P tetrahedra that share corners with two equivalent O(10)Na3MnP trigonal bipyramids,  an edgeedge with one O(20)Na3P tetrahedra, and  an edgeedge with one O(23)Na3MnP trigonal bipyramid. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(3), one Mn(2), and one P(1) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(2) atom. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(6), one Mn(2), and one P(2) atom to form distorted ONa3MnP trigonal bipyramids that share corners with two equivalent O(6)Na3P tetrahedra,  an edgeedge with one O(20)Na3P tetrahedra, and  an edgeedge with one O(23)Na3MnP trigonal bipyramid. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Na(6), one Mn(3), and one P(2) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Na(4), one Na(8), one Mn(3), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Na(4), one Na(5), one Mn(4), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Na(6), one Na(8), one Mn(3), and one P(4) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Na(8), one P(5), and one P(7) atom. In the sixteenth O site, O(16) is bonded in a distorted rectangular see-saw-like geometry to one Na(7), one Na(8), one Mn(1), and one P(7) atom. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Na(1), one Mn(4), and one P(7) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Na(3), one Na(4), one Mn(2), and one P(7) atom. In the nineteenth O site, O(19) is bonded in a 3-coordinate geometry to one Na(7), one Mn(3), and one P(5) atom. In the twentieth O site, O(20) is bonded to one Na(1), one Na(5), one Na(6), and one P(5) atom to form distorted ONa3P tetrahedra that share corners with two equivalent O(23)Na3MnP trigonal bipyramids,  an edgeedge with one O(6)Na3P tetrahedra, and  an edgeedge with one O(10)Na3MnP trigonal bipyramid. In the twenty-first O site, O(21) is bonded in a 4-coordinate geometry to one Na(3), one Na(4), one Mn(4), and one P(5) atom. In the twenty-second O site, O(22) is bonded in a bent 120 degrees geometry to one P(6) and one P(8) atom. In the twenty-third O site, O(23) is bonded to one Na(1), one Na(2), one Na(5), one Mn(4), and one P(6) atom to form distorted ONa3MnP trigonal bipyramids that share corners with two equivalent O(20)Na3P tetrahedra,  an edgeedge with one O(6)Na3P tetrahedra, and  an edgeedge with one O(10)Na3MnP trigonal bipyramid. In the twenty-fourth O site, O(24) is bonded in a 3-coordinate geometry to one Na(5), one Mn(1), and one P(6) atom. In the twenty-fifth O site, O(25) is bonded in a 4-coordinate geometry to one Na(4), one Mn(3), one Mn(4), and one P(6) atom. In the twenty-sixth O site, O(26) is bonded in a 4-coordinate geometry to one Na(3), one Na(6), one Mn(2), and one P(8) atom. In the twenty-seventh O site, O(27) is bonded in a 4-coordinate geometry to one Na(3), one Na(7), one Mn(1), and one P(8) atom. In the twenty-eighth O site, O(28) is bonded in a 3-coordinate geometry to one Na(5), one Mn(1), and one P(8) atom.
Na2MnP2O7 crystallizes in the triclinic P1 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to one O(10), one O(17), one O(20), and one O(23) atom. The Na(1)-O(10) bond length is 2.41 Å. The Na(1)-O(17) bond length is 2.29 Å. The Na(1)-O(20) bond length is 2.45 Å. The Na(1)-O(23) bond length is 2.61 Å. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(10), one O(23), one O(4), and one O(6) atom. The Na(2)-O(10) bond length is 2.58 Å. The Na(2)-O(23) bond length is 2.54 Å. The Na(2)-O(4) bond length is 2.29 Å. The Na(2)-O(6) bond length is 2.54 Å. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(18), one O(21), one O(26), one O(27), one O(3), and one O(7) atom. The Na(3)-O(18) bond length is 2.81 Å. The Na(3)-O(21) bond length is 2.76 Å. The Na(3)-O(26) bond length is 2.36 Å. The Na(3)-O(27) bond length is 2.73 Å. The Na(3)-O(3) bond length is 2.30 Å. The Na(3)-O(7) bond length is 2.53 Å. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(12), one O(13), one O(18), one O(21), and one O(25) atom. The Na(4)-O(12) bond length is 2.75 Å. The Na(4)-O(13) bond length is 2.34 Å. The Na(4)-O(18) bond length is 2.38 Å. The Na(4)-O(21) bond length is 2.61 Å. The Na(4)-O(25) bond length is 2.64 Å. In the fifth Na site, Na(5) is bonded to one O(13), one O(20), one O(23), one O(24), one O(28), and one O(6) atom to form distorted NaO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, corners with two equivalent P(6)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and  an edgeedge with one Mn(4)O6 octahedra. The Na(5)-O(13) bond length is 2.67 Å. The Na(5)-O(20) bond length is 2.50 Å. The Na(5)-O(23) bond length is 2.47 Å. The Na(5)-O(24) bond length is 2.35 Å. The Na(5)-O(28) bond length is 2.73 Å. The Na(5)-O(6) bond length is 2.36 Å. In the sixth Na site, Na(6) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(14), one O(20), one O(26), and one O(6) atom. The Na(6)-O(10) bond length is 2.55 Å. The Na(6)-O(11) bond length is 2.31 Å. The Na(6)-O(14) bond length is 2.77 Å. The Na(6)-O(20) bond length is 2.45 Å. The Na(6)-O(26) bond length is 2.63 Å. The Na(6)-O(6) bond length is 2.53 Å. In the seventh Na site, Na(7) is bonded in a 5-coordinate geometry to one O(16), one O(19), one O(2), one O(27), and one O(5) atom. The Na(7)-O(16) bond length is 2.42 Å. The Na(7)-O(19) bond length is 2.36 Å. The Na(7)-O(2) bond length is 2.39 Å. The Na(7)-O(27) bond length is 2.34 Å. The Na(7)-O(5) bond length is 2.69 Å. In the eighth Na site, Na(8) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(14), one O(15), one O(16), and one O(5) atom. The Na(8)-O(1) bond length is 2.25 Å. The Na(8)-O(12) bond length is 2.36 Å. The Na(8)-O(14) bond length is 2.86 Å. The Na(8)-O(15) bond length is 2.30 Å. The Na(8)-O(16) bond length is 2.50 Å. The Na(8)-O(5) bond length is 2.73 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(16), one O(24), one O(27), one O(28), one O(5), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, corners with two equivalent P(8)O4 tetrahedra, and  an edgeedge with one Na(5)O6 octahedra. The corner-sharing octahedral tilt angles are 65°. The Mn(1)-O(16) bond length is 2.32 Å. The Mn(1)-O(24) bond length is 2.23 Å. The Mn(1)-O(27) bond length is 2.27 Å. The Mn(1)-O(28) bond length is 2.14 Å. The Mn(1)-O(5) bond length is 2.23 Å. The Mn(1)-O(9) bond length is 2.29 Å. In the second Mn site, Mn(2) is bonded to one O(10), one O(18), one O(26), one O(4), one O(7), and one O(9) atom to form distorted MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. The Mn(2)-O(10) bond length is 2.44 Å. The Mn(2)-O(18) bond length is 2.11 Å. The Mn(2)-O(26) bond length is 2.17 Å. The Mn(2)-O(4) bond length is 2.12 Å. The Mn(2)-O(7) bond length is 2.12 Å. The Mn(2)-O(9) bond length is 2.26 Å. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(14), one O(19), one O(2), and one O(25) atom to form MnO6 octahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. The Mn(3)-O(11) bond length is 2.18 Å. The Mn(3)-O(12) bond length is 2.28 Å. The Mn(3)-O(14) bond length is 2.17 Å. The Mn(3)-O(19) bond length is 2.21 Å. The Mn(3)-O(2) bond length is 2.21 Å. The Mn(3)-O(25) bond length is 2.28 Å. In the fourth Mn site, Mn(4) is bonded to one O(13), one O(17), one O(21), one O(23), one O(25), and one O(3) atom to form MnO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra,  an edgeedge with one Na(5)O6 octahedra, and  an edgeedge with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. The Mn(4)-O(13) bond length is 2.19 Å. The Mn(4)-O(17) bond length is 2.17 Å. The Mn(4)-O(21) bond length is 2.11 Å. The Mn(4)-O(23) bond length is 2.36 Å. The Mn(4)-O(25) bond length is 2.29 Å. The Mn(4)-O(3) bond length is 2.10 Å. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-52°. The P(1)-O(1) bond length is 1.68 Å. The P(1)-O(5) bond length is 1.54 Å. The P(1)-O(6) bond length is 1.52 Å. The P(1)-O(7) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(10), one O(11), one O(8), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one P(4)O4 tetrahedra, and  an edgeedge with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. The P(2)-O(10) bond length is 1.55 Å. The P(2)-O(11) bond length is 1.52 Å. The P(2)-O(8) bond length is 1.62 Å. The P(2)-O(9) bond length is 1.55 Å. In the third P site, P(3) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-47°. The P(3)-O(1) bond length is 1.64 Å. The P(3)-O(2) bond length is 1.53 Å. The P(3)-O(3) bond length is 1.53 Å. The P(3)-O(4) bond length is 1.52 Å. In the fourth P site, P(4) is bonded to one O(12), one O(13), one O(14), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-56°. The P(4)-O(12) bond length is 1.55 Å. The P(4)-O(13) bond length is 1.53 Å. The P(4)-O(14) bond length is 1.53 Å. The P(4)-O(8) bond length is 1.62 Å. In the fifth P site, P(5) is bonded to one O(15), one O(19), one O(20), and one O(21) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-69°. The P(5)-O(15) bond length is 1.68 Å. The P(5)-O(19) bond length is 1.53 Å. The P(5)-O(20) bond length is 1.52 Å. The P(5)-O(21) bond length is 1.53 Å. In the sixth P site, P(6) is bonded to one O(22), one O(23), one O(24), and one O(25) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, corners with two equivalent Na(5)O6 octahedra,  a cornercorner with one P(8)O4 tetrahedra, and  an edgeedge with one Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. The P(6)-O(22) bond length is 1.61 Å. The P(6)-O(23) bond length is 1.55 Å. The P(6)-O(24) bond length is 1.53 Å. The P(6)-O(25) bond length is 1.55 Å. In the seventh P site, P(7) is bonded to one O(15), one O(16), one O(17), and one O(18) atom to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(4)O6 octahedra, and  a cornercorner with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-45°. The P(7)-O(15) bond length is 1.65 Å. The P(7)-O(16) bond length is 1.53 Å. The P(7)-O(17) bond length is 1.53 Å. The P(7)-O(18) bond length is 1.53 Å. In the eighth P site, P(8) is bonded to one O(22), one O(26), one O(27), and one O(28) atom to form PO4 tetrahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, and  a cornercorner with one P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-61°. The P(8)-O(22) bond length is 1.64 Å. The P(8)-O(26) bond length is 1.53 Å. The P(8)-O(27) bond length is 1.55 Å. The P(8)-O(28) bond length is 1.52 Å. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Na(8), one P(1), and one P(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(7), one Mn(3), and one P(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(3), one Mn(4), and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Na(2), one Mn(2), and one P(3) atom. In the fifth O site, O(5) is bonded in a 1-coordinate geometry to one Na(7), one Na(8), one Mn(1), and one P(1) atom. In the sixth O site, O(6) is bonded to one Na(2), one Na(5), one Na(6), and one P(1) atom to form distorted ONa3P tetrahedra that share corners with two equivalent O(10)Na3MnP trigonal bipyramids,  an edgeedge with one O(20)Na3P tetrahedra, and  an edgeedge with one O(23)Na3MnP trigonal bipyramid. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(3), one Mn(2), and one P(1) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(2) atom. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(6), one Mn(2), and one P(2) atom to form distorted ONa3MnP trigonal bipyramids that share corners with two equivalent O(6)Na3P tetrahedra,  an edgeedge with one O(20)Na3P tetrahedra, and  an edgeedge with one O(23)Na3MnP trigonal bipyramid. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Na(6), one Mn(3), and one P(2) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Na(4), one Na(8), one Mn(3), and one P(4) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Na(4), one Na(5), one Mn(4), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Na(6), one Na(8), one Mn(3), and one P(4) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Na(8), one P(5), and one P(7) atom. In the sixteenth O site, O(16) is bonded in a distorted rectangular see-saw-like geometry to one Na(7), one Na(8), one Mn(1), and one P(7) atom. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Na(1), one Mn(4), and one P(7) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Na(3), one Na(4), one Mn(2), and one P(7) atom. In the nineteenth O site, O(19) is bonded in a 3-coordinate geometry to one Na(7), one Mn(3), and one P(5) atom. In the twentieth O site, O(20) is bonded to one Na(1), one Na(5), one Na(6), and one P(5) atom to form distorted ONa3P tetrahedra that share corners with two equivalent O(23)Na3MnP trigonal bipyramids,  an edgeedge with one O(6)Na3P tetrahedra, and  an edgeedge with one O(10)Na3MnP trigonal bipyramid. In the twenty-first O site, O(21) is bonded in a 4-coordinate geometry to one Na(3), one Na(4), one Mn(4), and one P(5) atom. In the twenty-second O site, O(22) is bonded in a bent 120 degrees geometry to one P(6) and one P(8) atom. In the twenty-third O site, O(23) is bonded to one Na(1), one Na(2), one Na(5), one Mn(4), and one P(6) atom to form distorted ONa3MnP trigonal bipyramids that share corners with two equivalent O(20)Na3P tetrahedra,  an edgeedge with one O(6)Na3P tetrahedra, and  an edgeedge with one O(10)Na3MnP trigonal bipyramid. In the twenty-fourth O site, O(24) is bonded in a 3-coordinate geometry to one Na(5), one Mn(1), and one P(6) atom. In the twenty-fifth O site, O(25) is bonded in a 4-coordinate geometry to one Na(4), one Mn(3), one Mn(4), and one P(6) atom. In the twenty-sixth O site, O(26) is bonded in a 4-coordinate geometry to one Na(3), one Na(6), one Mn(2), and one P(8) atom. In the twenty-seventh O site, O(27) is bonded in a 4-coordinate geometry to one Na(3), one Na(7), one Mn(1), and one P(8) atom. In the twenty-eighth O site, O(28) is bonded in a 3-coordinate geometry to one Na(5), one Mn(1), and one P(8) atom.