The crystal structure described by Ca3MgFe2(CO3)6 is Calcite-derived structured and crystallizes in the trigonal P-3 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to six equivalent O(3) atoms to form CaO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. In the second Ca site, Ca(2) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form CaO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. Mg(1) is bonded to six equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. Fe(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form FeO6 octahedra that share corners with three equivalent Ca(1)O6 octahedra and corners with three equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. There are three inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to three equivalent O(3) atoms. In the second C site, C(2) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. In the third C site, C(3) is bonded in a trigonal planar geometry to three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(1), and one C(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(1), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3MgFe2(CO3)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.895
_cell_length_b   4.895
_cell_length_c   16.206
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   336.267
_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
  Ca  Ca0  1  0.000  0.000  0.500  1.0
  Ca  Ca1  1  0.667  0.333  0.834  1.0
  Ca  Ca2  1  0.333  0.667  0.166  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.667  0.333  0.333  1.0
  Fe  Fe5  1  0.333  0.667  0.667  1.0
  C  C6  1  0.667  0.333  0.590  1.0
  C  C7  1  0.333  0.667  0.923  1.0
  C  C8  1  0.000  0.000  0.256  1.0
  C  C9  1  0.000  0.000  0.744  1.0
  C  C10  1  0.667  0.333  0.077  1.0
  C  C11  1  0.333  0.667  0.410  1.0
  O  O12  1  0.613  0.915  0.922  1.0
  O  O13  1  0.278  0.251  0.255  1.0
  O  O14  1  0.944  0.585  0.588  1.0
  O  O15  1  0.302  0.387  0.922  1.0
  O  O16  1  0.974  0.722  0.255  1.0
  O  O17  1  0.640  0.056  0.588  1.0
  O  O18  1  0.085  0.698  0.922  1.0
  O  O19  1  0.749  0.026  0.255  1.0
  O  O20  1  0.415  0.360  0.588  1.0
  O  O21  1  0.387  0.085  0.078  1.0
  O  O22  1  0.056  0.415  0.412  1.0
  O  O23  1  0.722  0.749  0.745  1.0
  O  O24  1  0.698  0.613  0.078  1.0
  O  O25  1  0.360  0.944  0.412  1.0
  O  O26  1  0.026  0.278  0.745  1.0
  O  O27  1  0.915  0.302  0.078  1.0
  O  O28  1  0.585  0.640  0.412  1.0
  O  O29  1  0.251  0.974  0.745  1.0
[/CIF]
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The crystal structure described by Ca3MgFe2(CO3)6 is Calcite-derived structured and crystallizes in the trigonal P-3 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to six equivalent O(3) atoms to form CaO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. In the second Ca site, Ca(2) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form CaO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. Mg(1) is bonded to six equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. Fe(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form FeO6 octahedra that share corners with three equivalent Ca(1)O6 octahedra and corners with three equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. There are three inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to three equivalent O(3) atoms. In the second C site, C(2) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. In the third C site, C(3) is bonded in a trigonal planar geometry to three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(1), and one C(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(1), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3MgFe2(CO3)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.895
_cell_length_b   4.895
_cell_length_c   16.206
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   336.267
_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
  Ca  Ca0  1  0.000  0.000  0.500  1.0
  Ca  Ca1  1  0.667  0.333  0.834  1.0
  Ca  Ca2  1  0.333  0.667  0.166  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.667  0.333  0.333  1.0
  Fe  Fe5  1  0.333  0.667  0.667  1.0
  C  C6  1  0.667  0.333  0.590  1.0
  C  C7  1  0.333  0.667  0.923  1.0
  C  C8  1  0.000  0.000  0.256  1.0
  C  C9  1  0.000  0.000  0.744  1.0
  C  C10  1  0.667  0.333  0.077  1.0
  C  C11  1  0.333  0.667  0.410  1.0
  O  O12  1  0.613  0.915  0.922  1.0
  O  O13  1  0.278  0.251  0.255  1.0
  O  O14  1  0.944  0.585  0.588  1.0
  O  O15  1  0.302  0.387  0.922  1.0
  O  O16  1  0.974  0.722  0.255  1.0
  O  O17  1  0.640  0.056  0.588  1.0
  O  O18  1  0.085  0.698  0.922  1.0
  O  O19  1  0.749  0.026  0.255  1.0
  O  O20  1  0.415  0.360  0.588  1.0
  O  O21  1  0.387  0.085  0.078  1.0
  O  O22  1  0.056  0.415  0.412  1.0
  O  O23  1  0.722  0.749  0.745  1.0
  O  O24  1  0.698  0.613  0.078  1.0
  O  O25  1  0.360  0.944  0.412  1.0
  O  O26  1  0.026  0.278  0.745  1.0
  O  O27  1  0.915  0.302  0.078  1.0
  O  O28  1  0.585  0.640  0.412  1.0
  O  O29  1  0.251  0.974  0.745  1.0
[/CIF]
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