The compound described by MgCr4(PbO4)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(6) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(6), and one O(8) atom. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(2), one O(4), one O(5), and one O(7) atom. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 5-coordinate geometry to one O(2), one O(6), one O(7), and two equivalent O(3) atoms. In the second Pb site, Pb(2) is bonded in a 4-coordinate geometry to one O(5), one O(8), and two equivalent O(4) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in an L-shaped geometry to one Mg(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(2) and one Pb(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cr(1) and two equivalent Pb(1) atoms. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Cr(2) and two equivalent Pb(2) atoms. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Cr(2) and one Pb(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Pb(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Cr(2) and one Pb(1) atom. In the eighth O site, O(8) is bonded in a 1-coordinate geometry to one Cr(1) and one Pb(2) atom. is represented by the CIF file [CIF]
data_MgCr4(PbO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.983
_cell_length_b   7.371
_cell_length_c   7.943
_cell_angle_alpha   90.221
_cell_angle_beta   89.544
_cell_angle_gamma   103.462
_symmetry_Int_Tables_number   1
_cell_volume   397.589
_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
  Mg  Mg0  1  0.500  0.000  0.500  1.0
  Cr  Cr1  1  0.382  0.675  0.326  1.0
  Cr  Cr2  1  0.878  0.200  0.170  1.0
  Cr  Cr3  1  0.122  0.800  0.830  1.0
  Cr  Cr4  1  0.618  0.325  0.674  1.0
  Pb  Pb5  1  0.909  0.713  0.384  1.0
  Pb  Pb6  1  0.604  0.775  0.895  1.0
  Pb  Pb7  1  0.091  0.287  0.616  1.0
  Pb  Pb8  1  0.396  0.225  0.104  1.0
  O  O9  1  0.311  0.887  0.314  1.0
  O  O10  1  0.209  0.614  0.790  1.0
  O  O11  1  0.689  0.113  0.686  1.0
  O  O12  1  0.791  0.386  0.210  1.0
  O  O13  1  0.178  0.523  0.403  1.0
  O  O14  1  0.316  0.962  0.901  1.0
  O  O15  1  0.822  0.477  0.597  1.0
  O  O16  1  0.684  0.038  0.099  1.0
  O  O17  1  0.060  0.244  0.028  1.0
  O  O18  1  0.429  0.249  0.524  1.0
  O  O19  1  0.940  0.756  0.972  1.0
  O  O20  1  0.571  0.751  0.476  1.0
  O  O21  1  0.957  0.122  0.349  1.0
  O  O22  1  0.518  0.386  0.855  1.0
  O  O23  1  0.043  0.878  0.651  1.0
  O  O24  1  0.482  0.614  0.145  1.0
[/CIF]
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The compound described by MgCr4(PbO4)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(6) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(6), and one O(8) atom. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(2), one O(4), one O(5), and one O(7) atom. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 5-coordinate geometry to one O(2), one O(6), one O(7), and two equivalent O(3) atoms. In the second Pb site, Pb(2) is bonded in a 4-coordinate geometry to one O(5), one O(8), and two equivalent O(4) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in an L-shaped geometry to one Mg(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(2) and one Pb(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cr(1) and two equivalent Pb(1) atoms. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Cr(2) and two equivalent Pb(2) atoms. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Cr(2) and one Pb(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Pb(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Cr(2) and one Pb(1) atom. In the eighth O site, O(8) is bonded in a 1-coordinate geometry to one Cr(1) and one Pb(2) atom. is represented by the CIF file [CIF]
data_MgCr4(PbO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.983
_cell_length_b   7.371
_cell_length_c   7.943
_cell_angle_alpha   90.221
_cell_angle_beta   89.544
_cell_angle_gamma   103.462
_symmetry_Int_Tables_number   1
_cell_volume   397.589
_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
  Mg  Mg0  1  0.500  0.000  0.500  1.0
  Cr  Cr1  1  0.382  0.675  0.326  1.0
  Cr  Cr2  1  0.878  0.200  0.170  1.0
  Cr  Cr3  1  0.122  0.800  0.830  1.0
  Cr  Cr4  1  0.618  0.325  0.674  1.0
  Pb  Pb5  1  0.909  0.713  0.384  1.0
  Pb  Pb6  1  0.604  0.775  0.895  1.0
  Pb  Pb7  1  0.091  0.287  0.616  1.0
  Pb  Pb8  1  0.396  0.225  0.104  1.0
  O  O9  1  0.311  0.887  0.314  1.0
  O  O10  1  0.209  0.614  0.790  1.0
  O  O11  1  0.689  0.113  0.686  1.0
  O  O12  1  0.791  0.386  0.210  1.0
  O  O13  1  0.178  0.523  0.403  1.0
  O  O14  1  0.316  0.962  0.901  1.0
  O  O15  1  0.822  0.477  0.597  1.0
  O  O16  1  0.684  0.038  0.099  1.0
  O  O17  1  0.060  0.244  0.028  1.0
  O  O18  1  0.429  0.249  0.524  1.0
  O  O19  1  0.940  0.756  0.972  1.0
  O  O20  1  0.571  0.751  0.476  1.0
  O  O21  1  0.957  0.122  0.349  1.0
  O  O22  1  0.518  0.386  0.855  1.0
  O  O23  1  0.043  0.878  0.651  1.0
  O  O24  1  0.482  0.614  0.145  1.0
[/CIF]
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