The crystal structure described by NaMnO2 crystallizes in the monoclinic Pm space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(4), one O(7), two equivalent O(1), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(4)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mn(4)O5 square pyramids,  a faceface with one Mn(1)O5 square pyramid, and  a faceface with one Mn(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 45-49°. In the second Na site, Na(2) is bonded to one O(2), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share corners with three equivalent Na(4)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(2)O5 square pyramids,  an edgeedge with one Na(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-48°. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(7) atoms. In the fourth Na site, Na(4) is bonded to one O(2), one O(6), two equivalent O(4), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with three equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Mn(2)O5 square pyramids,  a faceface with one Mn(3)O6 octahedra, and  a faceface with one Mn(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 39-49°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(7), two equivalent O(1), and two equivalent O(5) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Mn(1)O5 square pyramids, and  a faceface with one Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-79°. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(2), and two equivalent O(6) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(4)O5 square pyramids, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Mn(2)O5 square pyramids, and  a faceface with one Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-86°. In the third Mn site, Mn(3) is bonded to one O(2), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(2)O5 square pyramids, edges with two equivalent Mn(3)O6 octahedra,  a faceface with one Na(4)O6 octahedra, and faces with two equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the fourth Mn site, Mn(4) is bonded to one O(6), two equivalent O(4), and two equivalent O(7) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with four equivalent Mn(2)O5 square pyramids, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mn(4)O5 square pyramids, and  a faceface with one Na(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-84°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), and two equivalent Mn(1) atoms to form distorted ONa3Mn2 trigonal bipyramids that share corners with three equivalent O(5)Na2Mn3 trigonal bipyramids,  an edgeedge with one O(5)Na2Mn3 trigonal bipyramid, and edges with two equivalent O(1)Na3Mn2 trigonal bipyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(2), one Na(4), one Mn(3), and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Na(2), two equivalent Na(3), and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(4), one Mn(2), and two equivalent Mn(4) atoms. In the fifth O site, O(5) is bonded to one Na(2), one Na(3), one Mn(3), and two equivalent Mn(1) atoms to form distorted ONa2Mn3 trigonal bipyramids that share corners with two equivalent O(5)Na2Mn3 trigonal bipyramids, corners with three equivalent O(1)Na3Mn2 trigonal bipyramids, and  an edgeedge with one O(1)Na3Mn2 trigonal bipyramid. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Na(4), two equivalent Na(1), one Mn(4), and two equivalent Mn(2) atoms. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(3), one Mn(1), and two equivalent Mn(4) atoms. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to two equivalent Na(2), two equivalent Na(4), and two equivalent Mn(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMnO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.886
_cell_length_b   5.821
_cell_length_c   11.483
_cell_angle_alpha   86.015
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   192.471
_cell_formula_units_Z   4
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  0.000  0.458  0.491  1.0
  Na  Na1  1  0.500  0.503  0.999  1.0
  Na  Na2  1  0.500  0.092  0.249  1.0
  Na  Na3  1  0.500  0.927  0.765  1.0
  Mn  Mn4  1  0.000  0.603  0.257  1.0
  Mn  Mn5  1  0.000  0.429  0.732  1.0
  Mn  Mn6  1  0.500  0.001  0.007  1.0
  Mn  Mn7  1  0.500  0.950  0.513  1.0
  O  O8  1  0.500  0.429  0.336  1.0
  O  O9  1  0.500  0.304  0.826  1.0
  O  O10  1  0.000  0.180  0.075  1.0
  O  O11  1  0.000  0.086  0.602  1.0
  O  O12  1  0.500  0.740  0.164  1.0
  O  O13  1  0.500  0.593  0.643  1.0
  O  O14  1  0.000  0.867  0.409  1.0
  O  O15  1  0.000  0.837  0.930  1.0
[/CIF]
.
The crystal structure described by NaMnO2 crystallizes in the monoclinic Pm space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(4), one O(7), two equivalent O(1), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(4)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mn(4)O5 square pyramids,  a faceface with one Mn(1)O5 square pyramid, and  a faceface with one Mn(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 45-49°. In the second Na site, Na(2) is bonded to one O(2), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share corners with three equivalent Na(4)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(2)O5 square pyramids,  an edgeedge with one Na(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-48°. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(7) atoms. In the fourth Na site, Na(4) is bonded to one O(2), one O(6), two equivalent O(4), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with three equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mn(4)O5 square pyramids,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Mn(2)O5 square pyramids,  a faceface with one Mn(3)O6 octahedra, and  a faceface with one Mn(4)O5 square pyramid. The corner-sharing octahedral tilt angles range from 39-49°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(7), two equivalent O(1), and two equivalent O(5) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(4)O5 square pyramids, edges with two equivalent Mn(1)O5 square pyramids, and  a faceface with one Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-79°. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(2), and two equivalent O(6) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, corners with four equivalent Mn(4)O5 square pyramids, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Mn(2)O5 square pyramids, and  a faceface with one Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-86°. In the third Mn site, Mn(3) is bonded to one O(2), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(2)O5 square pyramids, edges with two equivalent Mn(3)O6 octahedra,  a faceface with one Na(4)O6 octahedra, and faces with two equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the fourth Mn site, Mn(4) is bonded to one O(6), two equivalent O(4), and two equivalent O(7) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with four equivalent Mn(2)O5 square pyramids, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mn(4)O5 square pyramids, and  a faceface with one Na(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-84°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), and two equivalent Mn(1) atoms to form distorted ONa3Mn2 trigonal bipyramids that share corners with three equivalent O(5)Na2Mn3 trigonal bipyramids,  an edgeedge with one O(5)Na2Mn3 trigonal bipyramid, and edges with two equivalent O(1)Na3Mn2 trigonal bipyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(2), one Na(4), one Mn(3), and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Na(2), two equivalent Na(3), and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(4), one Mn(2), and two equivalent Mn(4) atoms. In the fifth O site, O(5) is bonded to one Na(2), one Na(3), one Mn(3), and two equivalent Mn(1) atoms to form distorted ONa2Mn3 trigonal bipyramids that share corners with two equivalent O(5)Na2Mn3 trigonal bipyramids, corners with three equivalent O(1)Na3Mn2 trigonal bipyramids, and  an edgeedge with one O(1)Na3Mn2 trigonal bipyramid. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Na(4), two equivalent Na(1), one Mn(4), and two equivalent Mn(2) atoms. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(3), one Mn(1), and two equivalent Mn(4) atoms. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to two equivalent Na(2), two equivalent Na(4), and two equivalent Mn(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMnO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.886
_cell_length_b   5.821
_cell_length_c   11.483
_cell_angle_alpha   86.015
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   192.471
_cell_formula_units_Z   4
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  0.000  0.458  0.491  1.0
  Na  Na1  1  0.500  0.503  0.999  1.0
  Na  Na2  1  0.500  0.092  0.249  1.0
  Na  Na3  1  0.500  0.927  0.765  1.0
  Mn  Mn4  1  0.000  0.603  0.257  1.0
  Mn  Mn5  1  0.000  0.429  0.732  1.0
  Mn  Mn6  1  0.500  0.001  0.007  1.0
  Mn  Mn7  1  0.500  0.950  0.513  1.0
  O  O8  1  0.500  0.429  0.336  1.0
  O  O9  1  0.500  0.304  0.826  1.0
  O  O10  1  0.000  0.180  0.075  1.0
  O  O11  1  0.000  0.086  0.602  1.0
  O  O12  1  0.500  0.740  0.164  1.0
  O  O13  1  0.500  0.593  0.643  1.0
  O  O14  1  0.000  0.867  0.409  1.0
  O  O15  1  0.000  0.837  0.930  1.0
[/CIF]
.