The structure described by Ca2MgFe(CO3)4 is Calcite-derived structured and crystallizes in the triclinic P1 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(16), one O(17), one O(23), one O(4), one O(6), and one O(9) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the second Ca site, Ca(2) is bonded to one O(10), one O(15), one O(18), one O(24), one O(3), and one O(5) atom to form CaO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the third Ca site, Ca(3) is bonded to one O(11), one O(14), one O(19), one O(2), one O(21), and one O(8) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the fourth Ca site, Ca(4) is bonded to one O(1), one O(12), one O(13), one O(20), one O(22), and one O(7) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, and corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(13), one O(19), one O(2), one O(22), one O(6), and one O(9) atom to form MgO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, and corners with two equivalent Ca(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. In the second Mg site, Mg(2) is bonded to one O(1), one O(10), one O(14), one O(20), one O(21), and one O(5) atom to form MgO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, and corners with two equivalent Ca(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(12), one O(16), one O(18), one O(23), one O(3), and one O(7) atom to form FeO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, and corners with two equivalent Ca(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the second Fe site, Fe(2) is bonded to one O(11), one O(15), one O(17), one O(24), one O(4), and one O(8) atom to form FeO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, and corners with two equivalent Ca(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. There are eight inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(21), one O(3), and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(10), one O(22), and one O(4) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(1), one O(11), and one O(23) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(12), one O(2), and one O(24) atom. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one O(13), one O(17), and one O(5) atom. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one O(14), one O(18), and one O(6) atom. In the seventh C site, C(7) is bonded in a trigonal planar geometry to one O(15), one O(19), and one O(7) atom. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one O(16), one O(20), and one O(8) atom. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(2), and one C(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(1), and one C(4) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ca(1), one Fe(2), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(2), and one C(5) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Mg(1), and one C(6) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Ca(4), one Fe(1), and one C(7) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Ca(3), one Fe(2), and one C(8) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Ca(1), one Mg(1), and one C(1) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(2), and one C(2) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Ca(3), one Fe(2), and one C(3) atom. In the twelfth O site, O(12) is bonded in a trigonal planar geometry to one Ca(4), one Fe(1), and one C(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(1), and one C(5) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(2), and one C(6) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(2), and one C(7) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(1), and one C(8) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(2), and one C(5) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(6) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(1), and one C(7) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(2), and one C(8) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(2), and one C(1) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(1), and one C(2) atom. In the twenty-third O site, O(23) is bonded in a trigonal planar geometry to one Ca(1), one Fe(1), and one C(3) atom. In the twenty-fourth O site, O(24) is bonded in a trigonal planar geometry to one Ca(2), one Fe(2), and one C(4) atom. is represented by the CIF file [CIF]
data_Ca2MgFe(CO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.884
_cell_length_b   6.114
_cell_length_c   7.846
_cell_angle_alpha   106.741
_cell_angle_beta   90.137
_cell_angle_gamma   90.454
_symmetry_Int_Tables_number   1
_cell_volume   224.342
_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
  C  C0  1  0.746  0.238  0.009  1.0
  C  C1  1  0.252  0.763  0.995  1.0
  C  C2  1  0.746  0.263  0.491  1.0
  C  C3  1  0.256  0.736  0.505  1.0
  Ca  Ca4  1  0.248  0.247  0.747  1.0
  Ca  Ca5  1  0.752  0.753  0.253  1.0
  Fe  Fe6  1  0.754  0.750  0.752  1.0
  Mg  Mg7  1  0.247  0.250  0.248  1.0
  O  O8  1  0.136  0.903  0.132  1.0
  O  O9  1  0.858  0.104  0.866  1.0
  O  O10  1  0.010  0.246  0.475  1.0
  O  O11  1  0.992  0.756  0.517  1.0
  O  O12  1  0.481  0.251  0.021  1.0
  O  O13  1  0.516  0.747  0.987  1.0
  O  O14  1  0.587  0.138  0.368  1.0
  O  O15  1  0.412  0.866  0.629  1.0
  O  O16  1  0.640  0.398  0.635  1.0
  O  O17  1  0.365  0.594  0.366  1.0
  O  O18  1  0.900  0.364  0.134  1.0
  O  O19  1  0.102  0.632  0.869  1.0
[/CIF]
.
The structure described by Ca2MgFe(CO3)4 is Calcite-derived structured and crystallizes in the triclinic P1 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(16), one O(17), one O(23), one O(4), one O(6), and one O(9) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the second Ca site, Ca(2) is bonded to one O(10), one O(15), one O(18), one O(24), one O(3), and one O(5) atom to form CaO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the third Ca site, Ca(3) is bonded to one O(11), one O(14), one O(19), one O(2), one O(21), and one O(8) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the fourth Ca site, Ca(4) is bonded to one O(1), one O(12), one O(13), one O(20), one O(22), and one O(7) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, and corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(13), one O(19), one O(2), one O(22), one O(6), and one O(9) atom to form MgO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, and corners with two equivalent Ca(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. In the second Mg site, Mg(2) is bonded to one O(1), one O(10), one O(14), one O(20), one O(21), and one O(5) atom to form MgO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, and corners with two equivalent Ca(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(12), one O(16), one O(18), one O(23), one O(3), and one O(7) atom to form FeO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, and corners with two equivalent Ca(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the second Fe site, Fe(2) is bonded to one O(11), one O(15), one O(17), one O(24), one O(4), and one O(8) atom to form FeO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, and corners with two equivalent Ca(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. There are eight inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(21), one O(3), and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(10), one O(22), and one O(4) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(1), one O(11), and one O(23) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(12), one O(2), and one O(24) atom. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one O(13), one O(17), and one O(5) atom. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one O(14), one O(18), and one O(6) atom. In the seventh C site, C(7) is bonded in a trigonal planar geometry to one O(15), one O(19), and one O(7) atom. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one O(16), one O(20), and one O(8) atom. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(2), and one C(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(1), and one C(4) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ca(1), one Fe(2), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(2), and one C(5) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Mg(1), and one C(6) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Ca(4), one Fe(1), and one C(7) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Ca(3), one Fe(2), and one C(8) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Ca(1), one Mg(1), and one C(1) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(2), and one C(2) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Ca(3), one Fe(2), and one C(3) atom. In the twelfth O site, O(12) is bonded in a trigonal planar geometry to one Ca(4), one Fe(1), and one C(4) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(1), and one C(5) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(2), and one C(6) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(2), and one C(7) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(1), and one C(8) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(2), and one C(5) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(6) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(1), and one C(7) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(2), and one C(8) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(2), and one C(1) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(1), and one C(2) atom. In the twenty-third O site, O(23) is bonded in a trigonal planar geometry to one Ca(1), one Fe(1), and one C(3) atom. In the twenty-fourth O site, O(24) is bonded in a trigonal planar geometry to one Ca(2), one Fe(2), and one C(4) atom. is represented by the CIF file [CIF]
data_Ca2MgFe(CO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.884
_cell_length_b   6.114
_cell_length_c   7.846
_cell_angle_alpha   106.741
_cell_angle_beta   90.137
_cell_angle_gamma   90.454
_symmetry_Int_Tables_number   1
_cell_volume   224.342
_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
  C  C0  1  0.746  0.238  0.009  1.0
  C  C1  1  0.252  0.763  0.995  1.0
  C  C2  1  0.746  0.263  0.491  1.0
  C  C3  1  0.256  0.736  0.505  1.0
  Ca  Ca4  1  0.248  0.247  0.747  1.0
  Ca  Ca5  1  0.752  0.753  0.253  1.0
  Fe  Fe6  1  0.754  0.750  0.752  1.0
  Mg  Mg7  1  0.247  0.250  0.248  1.0
  O  O8  1  0.136  0.903  0.132  1.0
  O  O9  1  0.858  0.104  0.866  1.0
  O  O10  1  0.010  0.246  0.475  1.0
  O  O11  1  0.992  0.756  0.517  1.0
  O  O12  1  0.481  0.251  0.021  1.0
  O  O13  1  0.516  0.747  0.987  1.0
  O  O14  1  0.587  0.138  0.368  1.0
  O  O15  1  0.412  0.866  0.629  1.0
  O  O16  1  0.640  0.398  0.635  1.0
  O  O17  1  0.365  0.594  0.366  1.0
  O  O18  1  0.900  0.364  0.134  1.0
  O  O19  1  0.102  0.632  0.869  1.0
[/CIF]
.