The crystal structure described by NaMn2O4 crystallizes in the monoclinic Cc space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(10), one O(12), one O(3), one O(4), one O(7), and one O(9) atom. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(3), one O(4), one O(8), and one O(9) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), and one O(5) atom. There are six inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form edge-sharing MnO6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted edge-sharing MnO6 octahedra. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(3), one O(7), one O(8), and one O(9) atom to form edge-sharing MnO6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(11), one O(12), one O(4), one O(7), and one O(8) atom to form edge-sharing MnO6 octahedra. In the fifth Mn site, Mn(5) is bonded to one O(1), one O(10), one O(11), one O(5), one O(6), and one O(9) atom to form edge-sharing MnO6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(10), one O(12), one O(2), one O(5), one O(6), and one O(9) atom to form edge-sharing MnO6 octahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), one Mn(1), one Mn(2), and one Mn(5) atom to form distorted ONaMn3 trigonal pyramids that share  a cornercorner with one O(12)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid, corners with two equivalent O(11)Na2Mn3 square pyramids, corners with two equivalent O(3)Na2Mn3 trigonal bipyramids,  a cornercorner with one O(2)NaMn3 trigonal pyramid,  an edgeedge with one O(10)Na3Mn3 octahedra,  an edgeedge with one O(4)Na2Mn3 square pyramid, and  an edgeedge with one O(2)NaMn3 trigonal pyramid. In the second O site, O(2) is bonded to one Na(3), one Mn(1), one Mn(2), and one Mn(6) atom to form distorted ONaMn3 trigonal pyramids that share  a cornercorner with one O(11)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid, corners with two equivalent O(12)Na2Mn3 square pyramids, corners with two equivalent O(4)Na2Mn3 square pyramids,  a cornercorner with one O(1)NaMn3 trigonal pyramid,  an edgeedge with one O(10)Na3Mn3 octahedra,  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid, and  an edgeedge with one O(1)NaMn3 trigonal pyramid. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Mn(1), one Mn(2), and one Mn(3) atom to form distorted ONa2Mn3 trigonal bipyramids that share corners with three equivalent O(9)Na2Mn3 square pyramids, corners with two equivalent O(1)NaMn3 trigonal pyramids,  an edgeedge with one O(10)Na3Mn3 octahedra,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(12)Na2Mn3 square pyramid, edges with two equivalent O(4)Na2Mn3 square pyramids, and  an edgeedge with one O(2)NaMn3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Mn(1), one Mn(2), and one Mn(4) atom to form ONa2Mn3 square pyramids that share corners with three equivalent O(10)Na3Mn3 octahedra, corners with two equivalent O(2)NaMn3 trigonal pyramids,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(12)Na2Mn3 square pyramid,  an edgeedge with one O(9)Na2Mn3 square pyramid, edges with two equivalent O(3)Na2Mn3 trigonal bipyramids, and  an edgeedge with one O(1)NaMn3 trigonal pyramid. The corner-sharing octahedral tilt angles range from 2-10°. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one Na(3), one Mn(1), one Mn(5), and one Mn(6) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mn(2), one Mn(5), and one Mn(6) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Mn(2), one Mn(3), and one Mn(4) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), one Mn(1), one Mn(3), and one Mn(4) atom. In the ninth O site, O(9) is bonded to one Na(1), one Na(2), one Mn(3), one Mn(5), and one Mn(6) atom to form ONa2Mn3 square pyramids that share  a cornercorner with one O(11)Na2Mn3 square pyramid,  a cornercorner with one O(12)Na2Mn3 square pyramid, corners with three equivalent O(3)Na2Mn3 trigonal bipyramids,  a cornercorner with one O(1)NaMn3 trigonal pyramid,  a cornercorner with one O(2)NaMn3 trigonal pyramid, edges with two equivalent O(10)Na3Mn3 octahedra,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(12)Na2Mn3 square pyramid, and  an edgeedge with one O(4)Na2Mn3 square pyramid. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(3), one Mn(4), one Mn(5), and one Mn(6) atom to form distorted ONa3Mn3 octahedra that share corners with three equivalent O(4)Na2Mn3 square pyramids, edges with two equivalent O(11)Na2Mn3 square pyramids, edges with two equivalent O(12)Na2Mn3 square pyramids, edges with two equivalent O(9)Na2Mn3 square pyramids,  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid,  an edgeedge with one O(1)NaMn3 trigonal pyramid, and  an edgeedge with one O(2)NaMn3 trigonal pyramid. In the eleventh O site, O(11) is bonded to one Na(2), one Na(3), one Mn(3), one Mn(4), and one Mn(5) atom to form distorted ONa2Mn3 square pyramids that share  a cornercorner with one O(12)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid,  a cornercorner with one O(2)NaMn3 trigonal pyramid, corners with two equivalent O(1)NaMn3 trigonal pyramids, edges with two equivalent O(10)Na3Mn3 octahedra,  an edgeedge with one O(12)Na2Mn3 square pyramid,  an edgeedge with one O(4)Na2Mn3 square pyramid,  an edgeedge with one O(9)Na2Mn3 square pyramid, and  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid. In the twelfth O site, O(12) is bonded to one Na(1), one Na(3), one Mn(3), one Mn(4), and one Mn(6) atom to form distorted ONa2Mn3 square pyramids that share  a cornercorner with one O(11)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid,  a cornercorner with one O(1)NaMn3 trigonal pyramid, corners with two equivalent O(2)NaMn3 trigonal pyramids, edges with two equivalent O(10)Na3Mn3 octahedra,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(4)Na2Mn3 square pyramid,  an edgeedge with one O(9)Na2Mn3 square pyramid, and  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.677
_cell_length_b   6.677
_cell_length_c   15.945
_cell_angle_alpha   72.871
_cell_angle_beta   72.871
_cell_angle_gamma   51.855
_symmetry_Int_Tables_number   1
_cell_volume   528.305
_cell_formula_units_Z   6
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Na  Na0  1  0.751  0.498  0.842  1.0
  Na  Na1  1  0.244  0.005  0.837  1.0
  Na  Na2  1  0.498  0.751  0.342  1.0
  Na  Na3  1  0.005  0.244  0.337  1.0
  Na  Na4  1  0.510  0.755  0.642  1.0
  Na  Na5  1  0.755  0.510  0.142  1.0
  Mn  Mn6  1  0.251  0.503  0.498  1.0
  Mn  Mn7  1  0.761  0.008  0.497  1.0
  Mn  Mn8  1  0.243  0.494  0.831  1.0
  Mn  Mn9  1  0.746  0.997  0.831  1.0
  Mn  Mn10  1  0.755  0.000  0.166  1.0
  Mn  Mn11  1  0.251  0.505  0.166  1.0
  Mn  Mn12  1  0.503  0.251  0.998  1.0
  Mn  Mn13  1  0.008  0.761  0.997  1.0
  Mn  Mn14  1  0.997  0.746  0.331  1.0
  Mn  Mn15  1  0.494  0.243  0.331  1.0
  Mn  Mn16  1  0.505  0.251  0.666  1.0
  Mn  Mn17  1  0.000  0.755  0.666  1.0
  O  O18  1  0.675  0.921  0.078  1.0
  O  O19  1  0.171  0.429  0.075  1.0
  O  O20  1  0.338  0.587  0.912  1.0
  O  O21  1  0.842  0.098  0.924  1.0
  O  O22  1  0.921  0.675  0.578  1.0
  O  O23  1  0.429  0.171  0.575  1.0
  O  O24  1  0.098  0.842  0.424  1.0
  O  O25  1  0.587  0.338  0.412  1.0
  O  O26  1  0.593  0.344  0.101  1.0
  O  O27  1  0.095  0.845  0.102  1.0
  O  O28  1  0.908  0.653  0.900  1.0
  O  O29  1  0.401  0.158  0.899  1.0
  O  O30  1  0.344  0.593  0.601  1.0
  O  O31  1  0.845  0.095  0.602  1.0
  O  O32  1  0.653  0.908  0.400  1.0
  O  O33  1  0.158  0.401  0.399  1.0
  O  O34  1  0.409  0.157  0.243  1.0
  O  O35  1  0.900  0.650  0.232  1.0
  O  O36  1  0.089  0.832  0.755  1.0
  O  O37  1  0.581  0.340  0.755  1.0
  O  O38  1  0.157  0.409  0.743  1.0
  O  O39  1  0.650  0.900  0.732  1.0
  O  O40  1  0.832  0.089  0.255  1.0
  O  O41  1  0.340  0.581  0.255  1.0
[/CIF]
.
The crystal structure described by NaMn2O4 crystallizes in the monoclinic Cc space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(10), one O(12), one O(3), one O(4), one O(7), and one O(9) atom. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(3), one O(4), one O(8), and one O(9) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), and one O(5) atom. There are six inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form edge-sharing MnO6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted edge-sharing MnO6 octahedra. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(3), one O(7), one O(8), and one O(9) atom to form edge-sharing MnO6 octahedra. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(11), one O(12), one O(4), one O(7), and one O(8) atom to form edge-sharing MnO6 octahedra. In the fifth Mn site, Mn(5) is bonded to one O(1), one O(10), one O(11), one O(5), one O(6), and one O(9) atom to form edge-sharing MnO6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(10), one O(12), one O(2), one O(5), one O(6), and one O(9) atom to form edge-sharing MnO6 octahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), one Mn(1), one Mn(2), and one Mn(5) atom to form distorted ONaMn3 trigonal pyramids that share  a cornercorner with one O(12)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid, corners with two equivalent O(11)Na2Mn3 square pyramids, corners with two equivalent O(3)Na2Mn3 trigonal bipyramids,  a cornercorner with one O(2)NaMn3 trigonal pyramid,  an edgeedge with one O(10)Na3Mn3 octahedra,  an edgeedge with one O(4)Na2Mn3 square pyramid, and  an edgeedge with one O(2)NaMn3 trigonal pyramid. In the second O site, O(2) is bonded to one Na(3), one Mn(1), one Mn(2), and one Mn(6) atom to form distorted ONaMn3 trigonal pyramids that share  a cornercorner with one O(11)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid, corners with two equivalent O(12)Na2Mn3 square pyramids, corners with two equivalent O(4)Na2Mn3 square pyramids,  a cornercorner with one O(1)NaMn3 trigonal pyramid,  an edgeedge with one O(10)Na3Mn3 octahedra,  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid, and  an edgeedge with one O(1)NaMn3 trigonal pyramid. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Mn(1), one Mn(2), and one Mn(3) atom to form distorted ONa2Mn3 trigonal bipyramids that share corners with three equivalent O(9)Na2Mn3 square pyramids, corners with two equivalent O(1)NaMn3 trigonal pyramids,  an edgeedge with one O(10)Na3Mn3 octahedra,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(12)Na2Mn3 square pyramid, edges with two equivalent O(4)Na2Mn3 square pyramids, and  an edgeedge with one O(2)NaMn3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Mn(1), one Mn(2), and one Mn(4) atom to form ONa2Mn3 square pyramids that share corners with three equivalent O(10)Na3Mn3 octahedra, corners with two equivalent O(2)NaMn3 trigonal pyramids,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(12)Na2Mn3 square pyramid,  an edgeedge with one O(9)Na2Mn3 square pyramid, edges with two equivalent O(3)Na2Mn3 trigonal bipyramids, and  an edgeedge with one O(1)NaMn3 trigonal pyramid. The corner-sharing octahedral tilt angles range from 2-10°. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one Na(3), one Mn(1), one Mn(5), and one Mn(6) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mn(2), one Mn(5), and one Mn(6) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Mn(2), one Mn(3), and one Mn(4) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), one Mn(1), one Mn(3), and one Mn(4) atom. In the ninth O site, O(9) is bonded to one Na(1), one Na(2), one Mn(3), one Mn(5), and one Mn(6) atom to form ONa2Mn3 square pyramids that share  a cornercorner with one O(11)Na2Mn3 square pyramid,  a cornercorner with one O(12)Na2Mn3 square pyramid, corners with three equivalent O(3)Na2Mn3 trigonal bipyramids,  a cornercorner with one O(1)NaMn3 trigonal pyramid,  a cornercorner with one O(2)NaMn3 trigonal pyramid, edges with two equivalent O(10)Na3Mn3 octahedra,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(12)Na2Mn3 square pyramid, and  an edgeedge with one O(4)Na2Mn3 square pyramid. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(3), one Mn(4), one Mn(5), and one Mn(6) atom to form distorted ONa3Mn3 octahedra that share corners with three equivalent O(4)Na2Mn3 square pyramids, edges with two equivalent O(11)Na2Mn3 square pyramids, edges with two equivalent O(12)Na2Mn3 square pyramids, edges with two equivalent O(9)Na2Mn3 square pyramids,  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid,  an edgeedge with one O(1)NaMn3 trigonal pyramid, and  an edgeedge with one O(2)NaMn3 trigonal pyramid. In the eleventh O site, O(11) is bonded to one Na(2), one Na(3), one Mn(3), one Mn(4), and one Mn(5) atom to form distorted ONa2Mn3 square pyramids that share  a cornercorner with one O(12)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid,  a cornercorner with one O(2)NaMn3 trigonal pyramid, corners with two equivalent O(1)NaMn3 trigonal pyramids, edges with two equivalent O(10)Na3Mn3 octahedra,  an edgeedge with one O(12)Na2Mn3 square pyramid,  an edgeedge with one O(4)Na2Mn3 square pyramid,  an edgeedge with one O(9)Na2Mn3 square pyramid, and  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid. In the twelfth O site, O(12) is bonded to one Na(1), one Na(3), one Mn(3), one Mn(4), and one Mn(6) atom to form distorted ONa2Mn3 square pyramids that share  a cornercorner with one O(11)Na2Mn3 square pyramid,  a cornercorner with one O(9)Na2Mn3 square pyramid,  a cornercorner with one O(1)NaMn3 trigonal pyramid, corners with two equivalent O(2)NaMn3 trigonal pyramids, edges with two equivalent O(10)Na3Mn3 octahedra,  an edgeedge with one O(11)Na2Mn3 square pyramid,  an edgeedge with one O(4)Na2Mn3 square pyramid,  an edgeedge with one O(9)Na2Mn3 square pyramid, and  an edgeedge with one O(3)Na2Mn3 trigonal bipyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMn2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.677
_cell_length_b   6.677
_cell_length_c   15.945
_cell_angle_alpha   72.871
_cell_angle_beta   72.871
_cell_angle_gamma   51.855
_symmetry_Int_Tables_number   1
_cell_volume   528.305
_cell_formula_units_Z   6
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Na  Na0  1  0.751  0.498  0.842  1.0
  Na  Na1  1  0.244  0.005  0.837  1.0
  Na  Na2  1  0.498  0.751  0.342  1.0
  Na  Na3  1  0.005  0.244  0.337  1.0
  Na  Na4  1  0.510  0.755  0.642  1.0
  Na  Na5  1  0.755  0.510  0.142  1.0
  Mn  Mn6  1  0.251  0.503  0.498  1.0
  Mn  Mn7  1  0.761  0.008  0.497  1.0
  Mn  Mn8  1  0.243  0.494  0.831  1.0
  Mn  Mn9  1  0.746  0.997  0.831  1.0
  Mn  Mn10  1  0.755  0.000  0.166  1.0
  Mn  Mn11  1  0.251  0.505  0.166  1.0
  Mn  Mn12  1  0.503  0.251  0.998  1.0
  Mn  Mn13  1  0.008  0.761  0.997  1.0
  Mn  Mn14  1  0.997  0.746  0.331  1.0
  Mn  Mn15  1  0.494  0.243  0.331  1.0
  Mn  Mn16  1  0.505  0.251  0.666  1.0
  Mn  Mn17  1  0.000  0.755  0.666  1.0
  O  O18  1  0.675  0.921  0.078  1.0
  O  O19  1  0.171  0.429  0.075  1.0
  O  O20  1  0.338  0.587  0.912  1.0
  O  O21  1  0.842  0.098  0.924  1.0
  O  O22  1  0.921  0.675  0.578  1.0
  O  O23  1  0.429  0.171  0.575  1.0
  O  O24  1  0.098  0.842  0.424  1.0
  O  O25  1  0.587  0.338  0.412  1.0
  O  O26  1  0.593  0.344  0.101  1.0
  O  O27  1  0.095  0.845  0.102  1.0
  O  O28  1  0.908  0.653  0.900  1.0
  O  O29  1  0.401  0.158  0.899  1.0
  O  O30  1  0.344  0.593  0.601  1.0
  O  O31  1  0.845  0.095  0.602  1.0
  O  O32  1  0.653  0.908  0.400  1.0
  O  O33  1  0.158  0.401  0.399  1.0
  O  O34  1  0.409  0.157  0.243  1.0
  O  O35  1  0.900  0.650  0.232  1.0
  O  O36  1  0.089  0.832  0.755  1.0
  O  O37  1  0.581  0.340  0.755  1.0
  O  O38  1  0.157  0.409  0.743  1.0
  O  O39  1  0.650  0.900  0.732  1.0
  O  O40  1  0.832  0.089  0.255  1.0
  O  O41  1  0.340  0.581  0.255  1.0
[/CIF]
.