The material structure described by NaCr2AlO10 crystallizes in the monoclinic C2/c space group. Na(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO8 hexagonal bipyramids that share corners with four equivalent Cr(1)O4 tetrahedra, edges with two equivalent Al(1)O6 octahedra, and edges with two equivalent Cr(1)O4 tetrahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with two equivalent Na(1)O8 hexagonal bipyramids, corners with two equivalent Al(1)O6 octahedra, and  an edgeedge with one Na(1)O8 hexagonal bipyramid. The corner-sharing octahedral tilt angles range from 33-44°. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with four equivalent Cr(1)O4 tetrahedra and edges with two equivalent Na(1)O8 hexagonal bipyramids. There are five inequivalent O sites. In the first O site, O(5) is bonded in a single-bond geometry to one Al(1) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Cr(1), and one Al(1) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Cr(1), and one Al(1) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one Cr(1) atom. In the fifth O site, O(4) is bonded in a single-bond geometry to one Na(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_NaAlCr2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.621
_cell_length_b   7.621
_cell_length_c   10.916
_cell_angle_alpha   70.977
_cell_angle_beta   70.977
_cell_angle_gamma   41.744
_symmetry_Int_Tables_number   1
_cell_volume   395.555
_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  0.784  0.216  0.250  1.0
  Na  Na1  1  0.216  0.784  0.750  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.500  1.0
  Cr  Cr4  1  0.360  0.840  0.039  1.0
  Cr  Cr5  1  0.160  0.640  0.461  1.0
  Cr  Cr6  1  0.640  0.160  0.961  1.0
  Cr  Cr7  1  0.840  0.360  0.539  1.0
  O  O8  1  0.149  0.178  0.570  1.0
  O  O9  1  0.822  0.851  0.930  1.0
  O  O10  1  0.851  0.822  0.430  1.0
  O  O11  1  0.178  0.149  0.070  1.0
  O  O12  1  0.679  0.603  0.079  1.0
  O  O13  1  0.397  0.321  0.421  1.0
  O  O14  1  0.321  0.397  0.921  1.0
  O  O15  1  0.603  0.679  0.579  1.0
  O  O16  1  0.848  0.375  0.385  1.0
  O  O17  1  0.625  0.152  0.115  1.0
  O  O18  1  0.152  0.625  0.615  1.0
  O  O19  1  0.375  0.848  0.885  1.0
  O  O20  1  0.211  0.755  0.126  1.0
  O  O21  1  0.245  0.789  0.374  1.0
  O  O22  1  0.789  0.245  0.874  1.0
  O  O23  1  0.755  0.211  0.626  1.0
  O  O24  1  0.012  0.548  0.157  1.0
  O  O25  1  0.452  0.988  0.343  1.0
  O  O26  1  0.988  0.452  0.843  1.0
  O  O27  1  0.548  0.012  0.657  1.0
[/CIF]
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The material structure described by NaCr2AlO10 crystallizes in the monoclinic C2/c space group. Na(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO8 hexagonal bipyramids that share corners with four equivalent Cr(1)O4 tetrahedra, edges with two equivalent Al(1)O6 octahedra, and edges with two equivalent Cr(1)O4 tetrahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with two equivalent Na(1)O8 hexagonal bipyramids, corners with two equivalent Al(1)O6 octahedra, and  an edgeedge with one Na(1)O8 hexagonal bipyramid. The corner-sharing octahedral tilt angles range from 33-44°. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with four equivalent Cr(1)O4 tetrahedra and edges with two equivalent Na(1)O8 hexagonal bipyramids. There are five inequivalent O sites. In the first O site, O(5) is bonded in a single-bond geometry to one Al(1) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Cr(1), and one Al(1) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Cr(1), and one Al(1) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one Cr(1) atom. In the fifth O site, O(4) is bonded in a single-bond geometry to one Na(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_NaAlCr2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.621
_cell_length_b   7.621
_cell_length_c   10.916
_cell_angle_alpha   70.977
_cell_angle_beta   70.977
_cell_angle_gamma   41.744
_symmetry_Int_Tables_number   1
_cell_volume   395.555
_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  0.784  0.216  0.250  1.0
  Na  Na1  1  0.216  0.784  0.750  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.500  1.0
  Cr  Cr4  1  0.360  0.840  0.039  1.0
  Cr  Cr5  1  0.160  0.640  0.461  1.0
  Cr  Cr6  1  0.640  0.160  0.961  1.0
  Cr  Cr7  1  0.840  0.360  0.539  1.0
  O  O8  1  0.149  0.178  0.570  1.0
  O  O9  1  0.822  0.851  0.930  1.0
  O  O10  1  0.851  0.822  0.430  1.0
  O  O11  1  0.178  0.149  0.070  1.0
  O  O12  1  0.679  0.603  0.079  1.0
  O  O13  1  0.397  0.321  0.421  1.0
  O  O14  1  0.321  0.397  0.921  1.0
  O  O15  1  0.603  0.679  0.579  1.0
  O  O16  1  0.848  0.375  0.385  1.0
  O  O17  1  0.625  0.152  0.115  1.0
  O  O18  1  0.152  0.625  0.615  1.0
  O  O19  1  0.375  0.848  0.885  1.0
  O  O20  1  0.211  0.755  0.126  1.0
  O  O21  1  0.245  0.789  0.374  1.0
  O  O22  1  0.789  0.245  0.874  1.0
  O  O23  1  0.755  0.211  0.626  1.0
  O  O24  1  0.012  0.548  0.157  1.0
  O  O25  1  0.452  0.988  0.343  1.0
  O  O26  1  0.988  0.452  0.843  1.0
  O  O27  1  0.548  0.012  0.657  1.0
[/CIF]
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