The compound described by NaCr12Si8O28Cl crystallizes in the tetragonal I4mm space group. Na(1) is bonded in a 4-coordinate geometry to four equivalent O(5) atoms. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a square co-planar geometry to two equivalent O(1), two equivalent O(3), and one Cl(1) atom. In the second Cr site, Cr(2) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. In the third Cr site, Cr(3) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(5), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(4), one O(5), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are five inequivalent O sites. In the first O site, O(4) is bonded in a trigonal planar geometry to two equivalent Cr(2) and one Si(2) atom. In the second O site, O(5) is bonded in a distorted trigonal planar geometry to one Na(1), one Si(1), and one Si(2) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(3), and one Si(2) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cr(3), and one Si(1) atom. In the fifth O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one Si(1) atom. Cl(1) is bonded in a 4-coordinate geometry to four equivalent Cr(1) atoms. is represented by the CIF card [CIF]
data_NaCr12Si8ClO28
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.910
_cell_length_b   9.910
_cell_length_c   9.910
_cell_angle_alpha   116.352
_cell_angle_beta   116.352
_cell_angle_gamma   96.444
_symmetry_Int_Tables_number   1
_cell_volume   721.220
_cell_formula_units_Z   1
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  0.041  0.041  0.000  1.0
  Cr  Cr1  1  0.285  0.058  0.772  1.0
  Cr  Cr2  1  0.285  0.513  0.228  1.0
  Cr  Cr3  1  0.513  0.285  0.228  1.0
  Cr  Cr4  1  0.058  0.285  0.772  1.0
  Cr  Cr5  1  0.718  0.950  0.232  1.0
  Cr  Cr6  1  0.718  0.486  0.768  1.0
  Cr  Cr7  1  0.486  0.718  0.768  1.0
  Cr  Cr8  1  0.950  0.718  0.232  1.0
  Cr  Cr9  1  0.499  0.176  0.676  1.0
  Cr  Cr10  1  0.499  0.823  0.324  1.0
  Cr  Cr11  1  0.823  0.499  0.324  1.0
  Cr  Cr12  1  0.176  0.499  0.676  1.0
  Si  Si13  1  0.892  0.892  0.562  1.0
  Si  Si14  1  0.330  0.330  0.438  1.0
  Si  Si15  1  0.330  0.892  0.000  1.0
  Si  Si16  1  0.892  0.330  0.000  1.0
  Si  Si17  1  0.106  0.106  0.435  1.0
  Si  Si18  1  0.672  0.672  0.565  1.0
  Si  Si19  1  0.672  0.106  0.000  1.0
  Si  Si20  1  0.106  0.672  0.000  1.0
  Cl  Cl21  1  0.437  0.437  0.000  1.0
  O  O22  1  0.254  0.069  0.557  1.0
  O  O23  1  0.511  0.697  0.443  1.0
  O  O24  1  0.511  0.069  0.815  1.0
  O  O25  1  0.254  0.697  0.185  1.0
  O  O26  1  0.697  0.254  0.185  1.0
  O  O27  1  0.069  0.511  0.815  1.0
  O  O28  1  0.069  0.254  0.557  1.0
  O  O29  1  0.697  0.511  0.443  1.0
  O  O30  1  0.744  0.928  0.439  1.0
  O  O31  1  0.490  0.306  0.561  1.0
  O  O32  1  0.490  0.928  0.184  1.0
  O  O33  1  0.744  0.306  0.816  1.0
  O  O34  1  0.306  0.744  0.816  1.0
  O  O35  1  0.928  0.490  0.184  1.0
  O  O36  1  0.928  0.744  0.439  1.0
  O  O37  1  0.306  0.490  0.561  1.0
  O  O38  1  0.058  0.058  0.716  1.0
  O  O39  1  0.343  0.343  0.284  1.0
  O  O40  1  0.343  0.058  0.000  1.0
  O  O41  1  0.058  0.343  0.000  1.0
  O  O42  1  0.941  0.941  0.287  1.0
  O  O43  1  0.654  0.654  0.713  1.0
  O  O44  1  0.654  0.941  0.000  1.0
  O  O45  1  0.941  0.654  0.000  1.0
  O  O46  1  0.836  0.836  0.671  1.0
  O  O47  1  0.165  0.165  0.329  1.0
  O  O48  1  0.165  0.836  0.000  1.0
  O  O49  1  0.836  0.165  0.000  1.0
[/CIF]
.
The compound described by NaCr12Si8O28Cl crystallizes in the tetragonal I4mm space group. Na(1) is bonded in a 4-coordinate geometry to four equivalent O(5) atoms. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a square co-planar geometry to two equivalent O(1), two equivalent O(3), and one Cl(1) atom. In the second Cr site, Cr(2) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. In the third Cr site, Cr(3) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(5), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(4), one O(5), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are five inequivalent O sites. In the first O site, O(4) is bonded in a trigonal planar geometry to two equivalent Cr(2) and one Si(2) atom. In the second O site, O(5) is bonded in a distorted trigonal planar geometry to one Na(1), one Si(1), and one Si(2) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(3), and one Si(2) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cr(3), and one Si(1) atom. In the fifth O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one Si(1) atom. Cl(1) is bonded in a 4-coordinate geometry to four equivalent Cr(1) atoms. is represented by the CIF card [CIF]
data_NaCr12Si8ClO28
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.910
_cell_length_b   9.910
_cell_length_c   9.910
_cell_angle_alpha   116.352
_cell_angle_beta   116.352
_cell_angle_gamma   96.444
_symmetry_Int_Tables_number   1
_cell_volume   721.220
_cell_formula_units_Z   1
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  0.041  0.041  0.000  1.0
  Cr  Cr1  1  0.285  0.058  0.772  1.0
  Cr  Cr2  1  0.285  0.513  0.228  1.0
  Cr  Cr3  1  0.513  0.285  0.228  1.0
  Cr  Cr4  1  0.058  0.285  0.772  1.0
  Cr  Cr5  1  0.718  0.950  0.232  1.0
  Cr  Cr6  1  0.718  0.486  0.768  1.0
  Cr  Cr7  1  0.486  0.718  0.768  1.0
  Cr  Cr8  1  0.950  0.718  0.232  1.0
  Cr  Cr9  1  0.499  0.176  0.676  1.0
  Cr  Cr10  1  0.499  0.823  0.324  1.0
  Cr  Cr11  1  0.823  0.499  0.324  1.0
  Cr  Cr12  1  0.176  0.499  0.676  1.0
  Si  Si13  1  0.892  0.892  0.562  1.0
  Si  Si14  1  0.330  0.330  0.438  1.0
  Si  Si15  1  0.330  0.892  0.000  1.0
  Si  Si16  1  0.892  0.330  0.000  1.0
  Si  Si17  1  0.106  0.106  0.435  1.0
  Si  Si18  1  0.672  0.672  0.565  1.0
  Si  Si19  1  0.672  0.106  0.000  1.0
  Si  Si20  1  0.106  0.672  0.000  1.0
  Cl  Cl21  1  0.437  0.437  0.000  1.0
  O  O22  1  0.254  0.069  0.557  1.0
  O  O23  1  0.511  0.697  0.443  1.0
  O  O24  1  0.511  0.069  0.815  1.0
  O  O25  1  0.254  0.697  0.185  1.0
  O  O26  1  0.697  0.254  0.185  1.0
  O  O27  1  0.069  0.511  0.815  1.0
  O  O28  1  0.069  0.254  0.557  1.0
  O  O29  1  0.697  0.511  0.443  1.0
  O  O30  1  0.744  0.928  0.439  1.0
  O  O31  1  0.490  0.306  0.561  1.0
  O  O32  1  0.490  0.928  0.184  1.0
  O  O33  1  0.744  0.306  0.816  1.0
  O  O34  1  0.306  0.744  0.816  1.0
  O  O35  1  0.928  0.490  0.184  1.0
  O  O36  1  0.928  0.744  0.439  1.0
  O  O37  1  0.306  0.490  0.561  1.0
  O  O38  1  0.058  0.058  0.716  1.0
  O  O39  1  0.343  0.343  0.284  1.0
  O  O40  1  0.343  0.058  0.000  1.0
  O  O41  1  0.058  0.343  0.000  1.0
  O  O42  1  0.941  0.941  0.287  1.0
  O  O43  1  0.654  0.654  0.713  1.0
  O  O44  1  0.654  0.941  0.000  1.0
  O  O45  1  0.941  0.654  0.000  1.0
  O  O46  1  0.836  0.836  0.671  1.0
  O  O47  1  0.165  0.165  0.329  1.0
  O  O48  1  0.165  0.836  0.000  1.0
  O  O49  1  0.836  0.165  0.000  1.0
[/CIF]
.