The compound described by NaMn4(AsO4)3 crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a square co-planar geometry to four equivalent O(3) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted MnO6 pentagonal pyramids that share corners with two equivalent As(1)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra, and edges with two equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(3), one O(5), one O(6), and two equivalent O(2) atoms to form MnO6 octahedra that share corners with two equivalent As(1)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra, and  an edgeedge with one Mn(1)O6 pentagonal pyramid. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(4) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to two equivalent O(1) and two equivalent O(6) atoms to form AsO4 tetrahedra that share corners with four equivalent Mn(2)O6 octahedra and corners with two equivalent Mn(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 59-63°. In the second As site, As(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form AsO4 tetrahedra that share corners with four equivalent Mn(2)O6 octahedra and corners with two equivalent Mn(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 44-60°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mn(2), one Mn(3), and one As(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Mn(2) and one As(2) atom. In the third O site, O(3) is bonded to two equivalent Na(1), one Mn(2), and one As(2) atom to form a mixture of distorted corner and edge-sharing ONa2MnAs trigonal pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mn(1), two equivalent Mn(3), and one As(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one As(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one As(1) atom. is represented by the CIF card [CIF]
data_NaMn4(AsO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.122
_cell_length_b   9.122
_cell_length_c   6.923
_cell_angle_alpha   72.864
_cell_angle_beta   72.864
_cell_angle_gamma   93.542
_symmetry_Int_Tables_number   1
_cell_volume   518.997
_cell_formula_units_Z   2
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  0.512  0.488  0.250  1.0
  Na  Na1  1  0.488  0.512  0.750  1.0
  Mn  Mn2  1  0.235  0.765  0.250  1.0
  Mn  Mn3  1  0.765  0.235  0.750  1.0
  Mn  Mn4  1  0.563  0.874  0.366  1.0
  Mn  Mn5  1  0.437  0.126  0.634  1.0
  Mn  Mn6  1  0.126  0.437  0.134  1.0
  Mn  Mn7  1  0.874  0.563  0.866  1.0
  Mn  Mn8  1  0.000  0.000  0.000  1.0
  Mn  Mn9  1  0.000  0.000  0.500  1.0
  As  As10  1  0.792  0.208  0.250  1.0
  As  As11  1  0.208  0.792  0.750  1.0
  As  As12  1  0.378  0.158  0.132  1.0
  As  As13  1  0.622  0.842  0.868  1.0
  As  As14  1  0.842  0.622  0.368  1.0
  As  As15  1  0.158  0.378  0.632  1.0
  O  O16  1  0.785  0.024  0.220  1.0
  O  O17  1  0.215  0.976  0.780  1.0
  O  O18  1  0.976  0.215  0.280  1.0
  O  O19  1  0.024  0.785  0.720  1.0
  O  O20  1  0.460  0.094  0.328  1.0
  O  O21  1  0.540  0.906  0.672  1.0
  O  O22  1  0.906  0.540  0.172  1.0
  O  O23  1  0.094  0.460  0.828  1.0
  O  O24  1  0.657  0.660  0.393  1.0
  O  O25  1  0.343  0.340  0.607  1.0
  O  O26  1  0.340  0.343  0.107  1.0
  O  O27  1  0.660  0.657  0.893  1.0
  O  O28  1  0.208  0.024  0.205  1.0
  O  O29  1  0.792  0.976  0.795  1.0
  O  O30  1  0.976  0.792  0.295  1.0
  O  O31  1  0.024  0.208  0.705  1.0
  O  O32  1  0.491  0.832  0.112  1.0
  O  O33  1  0.509  0.168  0.888  1.0
  O  O34  1  0.168  0.509  0.388  1.0
  O  O35  1  0.832  0.491  0.612  1.0
  O  O36  1  0.677  0.242  0.473  1.0
  O  O37  1  0.323  0.758  0.527  1.0
  O  O38  1  0.758  0.323  0.027  1.0
  O  O39  1  0.242  0.677  0.973  1.0
[/CIF]
.
The compound described by NaMn4(AsO4)3 crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a square co-planar geometry to four equivalent O(3) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form distorted MnO6 pentagonal pyramids that share corners with two equivalent As(1)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra, and edges with two equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(3), one O(5), one O(6), and two equivalent O(2) atoms to form MnO6 octahedra that share corners with two equivalent As(1)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra,  an edgeedge with one Mn(2)O6 octahedra, and  an edgeedge with one Mn(1)O6 pentagonal pyramid. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(4) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to two equivalent O(1) and two equivalent O(6) atoms to form AsO4 tetrahedra that share corners with four equivalent Mn(2)O6 octahedra and corners with two equivalent Mn(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 59-63°. In the second As site, As(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form AsO4 tetrahedra that share corners with four equivalent Mn(2)O6 octahedra and corners with two equivalent Mn(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 44-60°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mn(2), one Mn(3), and one As(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Mn(2) and one As(2) atom. In the third O site, O(3) is bonded to two equivalent Na(1), one Mn(2), and one As(2) atom to form a mixture of distorted corner and edge-sharing ONa2MnAs trigonal pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mn(1), two equivalent Mn(3), and one As(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one As(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one As(1) atom. is represented by the CIF card [CIF]
data_NaMn4(AsO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.122
_cell_length_b   9.122
_cell_length_c   6.923
_cell_angle_alpha   72.864
_cell_angle_beta   72.864
_cell_angle_gamma   93.542
_symmetry_Int_Tables_number   1
_cell_volume   518.997
_cell_formula_units_Z   2
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  0.512  0.488  0.250  1.0
  Na  Na1  1  0.488  0.512  0.750  1.0
  Mn  Mn2  1  0.235  0.765  0.250  1.0
  Mn  Mn3  1  0.765  0.235  0.750  1.0
  Mn  Mn4  1  0.563  0.874  0.366  1.0
  Mn  Mn5  1  0.437  0.126  0.634  1.0
  Mn  Mn6  1  0.126  0.437  0.134  1.0
  Mn  Mn7  1  0.874  0.563  0.866  1.0
  Mn  Mn8  1  0.000  0.000  0.000  1.0
  Mn  Mn9  1  0.000  0.000  0.500  1.0
  As  As10  1  0.792  0.208  0.250  1.0
  As  As11  1  0.208  0.792  0.750  1.0
  As  As12  1  0.378  0.158  0.132  1.0
  As  As13  1  0.622  0.842  0.868  1.0
  As  As14  1  0.842  0.622  0.368  1.0
  As  As15  1  0.158  0.378  0.632  1.0
  O  O16  1  0.785  0.024  0.220  1.0
  O  O17  1  0.215  0.976  0.780  1.0
  O  O18  1  0.976  0.215  0.280  1.0
  O  O19  1  0.024  0.785  0.720  1.0
  O  O20  1  0.460  0.094  0.328  1.0
  O  O21  1  0.540  0.906  0.672  1.0
  O  O22  1  0.906  0.540  0.172  1.0
  O  O23  1  0.094  0.460  0.828  1.0
  O  O24  1  0.657  0.660  0.393  1.0
  O  O25  1  0.343  0.340  0.607  1.0
  O  O26  1  0.340  0.343  0.107  1.0
  O  O27  1  0.660  0.657  0.893  1.0
  O  O28  1  0.208  0.024  0.205  1.0
  O  O29  1  0.792  0.976  0.795  1.0
  O  O30  1  0.976  0.792  0.295  1.0
  O  O31  1  0.024  0.208  0.705  1.0
  O  O32  1  0.491  0.832  0.112  1.0
  O  O33  1  0.509  0.168  0.888  1.0
  O  O34  1  0.168  0.509  0.388  1.0
  O  O35  1  0.832  0.491  0.612  1.0
  O  O36  1  0.677  0.242  0.473  1.0
  O  O37  1  0.323  0.758  0.527  1.0
  O  O38  1  0.758  0.323  0.027  1.0
  O  O39  1  0.242  0.677  0.973  1.0
[/CIF]
.