The structure described by Ca2MgFe(CO3)4 is Calcite-derived structured and crystallizes in the triclinic P1 space group. There are eight inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(17), one O(32), one O(33), one O(45), one O(5), and one O(9) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, and corners with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-62°. In the second Ca site, Ca(2) is bonded to one O(10), one O(18), one O(29), one O(34), one O(46), and one O(6) 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(3)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(19), one O(30), one O(35), one O(47), and one O(7) atom to form CaO6 octahedra that share corners with two equivalent Mg(3)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 61-62°. In the fourth Ca site, Ca(4) is bonded to one O(12), one O(20), one O(31), one O(36), one O(48), and one O(8) atom to form CaO6 octahedra that share corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, and corners with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the fifth Ca site, Ca(5) is bonded to one O(1), one O(13), one O(21), one O(26), one O(37), and one O(41) 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(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the sixth Ca site, Ca(6) is bonded to one O(14), one O(2), one O(22), one O(27), one O(38), and one O(42) atom to form CaO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, and corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the seventh Ca site, Ca(7) is bonded to one O(15), one O(23), one O(28), one O(3), one O(39), and one O(43) atom to form CaO6 octahedra that share corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the eighth Ca site, Ca(8) is bonded to one O(16), one O(24), one O(25), one O(4), one O(40), and one O(44) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, and corners with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(17), one O(25), one O(37), one O(4), one O(41), and one O(9) atom to form MgO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, and corners with two equivalent Ca(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the second Mg site, Mg(2) is bonded to one O(1), one O(10), one O(18), one O(26), one O(38), and one O(42) atom to form MgO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, and corners with two equivalent Ca(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the third Mg site, Mg(3) is bonded to one O(11), one O(19), one O(2), one O(27), one O(39), and one O(43) atom to form MgO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Ca(6)O6 octahedra, and corners with two equivalent Ca(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the fourth Mg site, Mg(4) is bonded to one O(12), one O(20), one O(28), one O(3), one O(40), and one O(44) atom to form MgO6 octahedra that share corners with two equivalent Ca(4)O6 octahedra, corners with two equivalent Ca(7)O6 octahedra, and corners with two equivalent Ca(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(14), one O(22), one O(30), one O(34), one O(46), and one O(7) atom to form FeO6 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(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the second Fe site, Fe(2) is bonded to one O(15), one O(23), one O(31), one O(35), one O(47), and one O(8) atom to form FeO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Ca(4)O6 octahedra, and corners with two equivalent Ca(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-63°. In the third Fe site, Fe(3) is bonded to one O(13), one O(21), one O(29), one O(33), one O(45), and one O(6) 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(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the fourth Fe site, Fe(4) is bonded to one O(16), one O(24), one O(32), one O(36), one O(48), and one O(5) atom to form FeO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(4)O6 octahedra, and corners with two equivalent Ca(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are sixteen inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(17), one O(41), and one O(5) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(18), one O(42), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(19), one O(43), and one O(7) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(20), one O(44), and one O(8) atom. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one O(1), one O(21), and one O(45) atom. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one O(2), one O(22), and one O(46) atom. In the seventh C site, C(7) is bonded in a trigonal planar geometry to one O(23), one O(3), and one O(47) atom. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one O(24), one O(4), and one O(48) atom. In the ninth C site, C(9) is bonded in a trigonal planar geometry to one O(25), one O(33), and one O(9) atom. In the tenth C site, C(10) is bonded in a trigonal planar geometry to one O(10), one O(26), and one O(34) atom. In the eleventh C site, C(11) is bonded in a trigonal planar geometry to one O(11), one O(27), and one O(35) atom. In the twelfth C site, C(12) is bonded in a trigonal planar geometry to one O(12), one O(28), and one O(36) atom. In the thirteenth C site, C(13) is bonded in a trigonal planar geometry to one O(13), one O(29), and one O(37) atom. In the fourteenth C site, C(14) is bonded in a trigonal planar geometry to one O(14), one O(30), and one O(38) atom. In the fifteenth C site, C(15) is bonded in a trigonal planar geometry to one O(15), one O(31), and one O(39) atom. In the sixteenth C site, C(16) is bonded in a trigonal planar geometry to one O(16), one O(32), and one O(40) atom. There are forty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(2), and one C(5) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(3), and one C(6) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(4), and one C(7) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(1), and one C(8) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Ca(1), one Fe(4), and one C(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Ca(2), one Fe(3), and one C(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Ca(3), one Fe(1), and one C(3) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Ca(4), one Fe(2), and one C(4) 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(9) 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(10) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(3), and one C(11) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(4), and one C(12) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Ca(5), one Fe(3), and one C(13) atom. In the fourteenth O site, O(14) is bonded in a trigonal planar geometry to one Ca(6), one Fe(1), and one C(14) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Ca(7), one Fe(2), and one C(15) atom. In the sixteenth O site, O(16) is bonded in a trigonal planar geometry to one Ca(8), one Fe(4), and one C(16) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal planar geometry to one Ca(1), one Mg(1), and one C(1) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(2), and one C(2) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(3), and one C(3) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(4), and one C(4) atom. In the twenty-first O site, O(21) is bonded in a trigonal planar geometry to one Ca(5), one Fe(3), and one C(5) atom. In the twenty-second O site, O(22) is bonded in a trigonal planar geometry to one Ca(6), one Fe(1), and one C(6) atom. In the twenty-third O site, O(23) is bonded in a trigonal planar geometry to one Ca(7), one Fe(2), and one C(7) atom. In the twenty-fourth O site, O(24) is bonded in a trigonal planar geometry to one Ca(8), one Fe(4), and one C(8) atom. In the twenty-fifth O site, O(25) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(1), and one C(9) atom. In the twenty-sixth O site, O(26) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(2), and one C(10) atom. In the twenty-seventh O site, O(27) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(3), and one C(11) atom. In the twenty-eighth O site, O(28) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(4), and one C(12) atom. In the twenty-ninth O site, O(29) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(3), and one C(13) atom. In the thirtieth O site, O(30) is bonded in a trigonal planar geometry to one Ca(3), one Fe(1), and one C(14) atom. In the thirty-first O site, O(31) is bonded in a distorted trigonal planar geometry to one Ca(4), one Fe(2), and one C(15) atom. In the thirty-second O site, O(32) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(4), and one C(16) atom. In the thirty-third O site, O(33) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(3), and one C(9) atom. In the thirty-fourth O site, O(34) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(10) atom. In the thirty-fifth O site, O(35) is bonded in a distorted trigonal planar geometry to one Ca(3), one Fe(2), and one C(11) atom. In the thirty-sixth O site, O(36) is bonded in a distorted trigonal planar geometry to one Ca(4), one Fe(4), and one C(12) atom. In the thirty-seventh O site, O(37) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(1), and one C(13) atom. In the thirty-eighth O site, O(38) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(2), and one C(14) atom. In the thirty-ninth O site, O(39) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(3), and one C(15) atom. In the fortieth O site, O(40) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(4), and one C(16) atom. In the forty-first O site, O(41) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(1), and one C(1) atom. In the forty-second O site, O(42) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(2), and one C(2) atom. In the forty-third O site, O(43) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(3), and one C(3) atom. In the forty-fourth O site, O(44) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(4), and one C(4) atom. In the forty-fifth O site, O(45) is bonded in a trigonal planar geometry to one Ca(1), one Fe(3), and one C(5) atom. In the forty-sixth O site, O(46) is bonded in a trigonal planar geometry to one Ca(2), one Fe(1), and one C(6) atom. In the forty-seventh O site, O(47) is bonded in a trigonal planar geometry to one Ca(3), one Fe(2), and one C(7) atom. In the forty-eighth O site, O(48) is bonded in a trigonal planar geometry to one Ca(4), one Fe(4), and one C(8) atom. is represented by the CIF card [CIF]
data_Ca2MgFe(CO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.887
_cell_length_b   6.115
_cell_length_c   7.840
_cell_angle_alpha   106.626
_cell_angle_beta   89.967
_cell_angle_gamma   89.817
_symmetry_Int_Tables_number   1
_cell_volume   224.465
_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  0.747  0.763  0.992  1.0
  C  C1  1  0.253  0.237  0.004  1.0
  C  C2  1  0.747  0.737  0.509  1.0
  C  C3  1  0.254  0.264  0.496  1.0
  Ca  Ca4  1  0.248  0.753  0.253  1.0
  Ca  Ca5  1  0.752  0.248  0.747  1.0
  Fe  Fe6  1  0.753  0.250  0.249  1.0
  Mg  Mg7  1  0.247  0.750  0.752  1.0
  O  O8  1  0.138  0.097  0.867  1.0
  O  O9  1  0.860  0.897  0.134  1.0
  O  O10  1  0.011  0.753  0.525  1.0
  O  O11  1  0.990  0.244  0.483  1.0
  O  O12  1  0.482  0.749  0.979  1.0
  O  O13  1  0.517  0.253  0.013  1.0
  O  O14  1  0.589  0.862  0.632  1.0
  O  O15  1  0.408  0.135  0.372  1.0
  O  O16  1  0.639  0.602  0.365  1.0
  O  O17  1  0.362  0.405  0.635  1.0
  O  O18  1  0.901  0.637  0.867  1.0
  O  O19  1  0.103  0.367  0.130  1.0
[/CIF]
.
The structure described by Ca2MgFe(CO3)4 is Calcite-derived structured and crystallizes in the triclinic P1 space group. There are eight inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(17), one O(32), one O(33), one O(45), one O(5), and one O(9) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, and corners with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-62°. In the second Ca site, Ca(2) is bonded to one O(10), one O(18), one O(29), one O(34), one O(46), and one O(6) 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(3)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(19), one O(30), one O(35), one O(47), and one O(7) atom to form CaO6 octahedra that share corners with two equivalent Mg(3)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 61-62°. In the fourth Ca site, Ca(4) is bonded to one O(12), one O(20), one O(31), one O(36), one O(48), and one O(8) atom to form CaO6 octahedra that share corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, and corners with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the fifth Ca site, Ca(5) is bonded to one O(1), one O(13), one O(21), one O(26), one O(37), and one O(41) 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(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the sixth Ca site, Ca(6) is bonded to one O(14), one O(2), one O(22), one O(27), one O(38), and one O(42) atom to form CaO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, and corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the seventh Ca site, Ca(7) is bonded to one O(15), one O(23), one O(28), one O(3), one O(39), and one O(43) atom to form CaO6 octahedra that share corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the eighth Ca site, Ca(8) is bonded to one O(16), one O(24), one O(25), one O(4), one O(40), and one O(44) atom to form CaO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, and corners with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(17), one O(25), one O(37), one O(4), one O(41), and one O(9) atom to form MgO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, and corners with two equivalent Ca(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the second Mg site, Mg(2) is bonded to one O(1), one O(10), one O(18), one O(26), one O(38), and one O(42) atom to form MgO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, and corners with two equivalent Ca(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the third Mg site, Mg(3) is bonded to one O(11), one O(19), one O(2), one O(27), one O(39), and one O(43) atom to form MgO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Ca(6)O6 octahedra, and corners with two equivalent Ca(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the fourth Mg site, Mg(4) is bonded to one O(12), one O(20), one O(28), one O(3), one O(40), and one O(44) atom to form MgO6 octahedra that share corners with two equivalent Ca(4)O6 octahedra, corners with two equivalent Ca(7)O6 octahedra, and corners with two equivalent Ca(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(14), one O(22), one O(30), one O(34), one O(46), and one O(7) atom to form FeO6 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(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the second Fe site, Fe(2) is bonded to one O(15), one O(23), one O(31), one O(35), one O(47), and one O(8) atom to form FeO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Ca(4)O6 octahedra, and corners with two equivalent Ca(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-63°. In the third Fe site, Fe(3) is bonded to one O(13), one O(21), one O(29), one O(33), one O(45), and one O(6) 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(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-63°. In the fourth Fe site, Fe(4) is bonded to one O(16), one O(24), one O(32), one O(36), one O(48), and one O(5) atom to form FeO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(4)O6 octahedra, and corners with two equivalent Ca(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are sixteen inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(17), one O(41), and one O(5) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(18), one O(42), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(19), one O(43), and one O(7) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(20), one O(44), and one O(8) atom. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one O(1), one O(21), and one O(45) atom. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one O(2), one O(22), and one O(46) atom. In the seventh C site, C(7) is bonded in a trigonal planar geometry to one O(23), one O(3), and one O(47) atom. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one O(24), one O(4), and one O(48) atom. In the ninth C site, C(9) is bonded in a trigonal planar geometry to one O(25), one O(33), and one O(9) atom. In the tenth C site, C(10) is bonded in a trigonal planar geometry to one O(10), one O(26), and one O(34) atom. In the eleventh C site, C(11) is bonded in a trigonal planar geometry to one O(11), one O(27), and one O(35) atom. In the twelfth C site, C(12) is bonded in a trigonal planar geometry to one O(12), one O(28), and one O(36) atom. In the thirteenth C site, C(13) is bonded in a trigonal planar geometry to one O(13), one O(29), and one O(37) atom. In the fourteenth C site, C(14) is bonded in a trigonal planar geometry to one O(14), one O(30), and one O(38) atom. In the fifteenth C site, C(15) is bonded in a trigonal planar geometry to one O(15), one O(31), and one O(39) atom. In the sixteenth C site, C(16) is bonded in a trigonal planar geometry to one O(16), one O(32), and one O(40) atom. There are forty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(2), and one C(5) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(3), and one C(6) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(4), and one C(7) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(1), and one C(8) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Ca(1), one Fe(4), and one C(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Ca(2), one Fe(3), and one C(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Ca(3), one Fe(1), and one C(3) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Ca(4), one Fe(2), and one C(4) 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(9) 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(10) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(3), and one C(11) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(4), and one C(12) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Ca(5), one Fe(3), and one C(13) atom. In the fourteenth O site, O(14) is bonded in a trigonal planar geometry to one Ca(6), one Fe(1), and one C(14) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Ca(7), one Fe(2), and one C(15) atom. In the sixteenth O site, O(16) is bonded in a trigonal planar geometry to one Ca(8), one Fe(4), and one C(16) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal planar geometry to one Ca(1), one Mg(1), and one C(1) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal planar geometry to one Ca(2), one Mg(2), and one C(2) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Ca(3), one Mg(3), and one C(3) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Ca(4), one Mg(4), and one C(4) atom. In the twenty-first O site, O(21) is bonded in a trigonal planar geometry to one Ca(5), one Fe(3), and one C(5) atom. In the twenty-second O site, O(22) is bonded in a trigonal planar geometry to one Ca(6), one Fe(1), and one C(6) atom. In the twenty-third O site, O(23) is bonded in a trigonal planar geometry to one Ca(7), one Fe(2), and one C(7) atom. In the twenty-fourth O site, O(24) is bonded in a trigonal planar geometry to one Ca(8), one Fe(4), and one C(8) atom. In the twenty-fifth O site, O(25) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(1), and one C(9) atom. In the twenty-sixth O site, O(26) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(2), and one C(10) atom. In the twenty-seventh O site, O(27) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(3), and one C(11) atom. In the twenty-eighth O site, O(28) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(4), and one C(12) atom. In the twenty-ninth O site, O(29) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(3), and one C(13) atom. In the thirtieth O site, O(30) is bonded in a trigonal planar geometry to one Ca(3), one Fe(1), and one C(14) atom. In the thirty-first O site, O(31) is bonded in a distorted trigonal planar geometry to one Ca(4), one Fe(2), and one C(15) atom. In the thirty-second O site, O(32) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(4), and one C(16) atom. In the thirty-third O site, O(33) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(3), and one C(9) atom. In the thirty-fourth O site, O(34) is bonded in a distorted trigonal planar geometry to one Ca(2), one Fe(1), and one C(10) atom. In the thirty-fifth O site, O(35) is bonded in a distorted trigonal planar geometry to one Ca(3), one Fe(2), and one C(11) atom. In the thirty-sixth O site, O(36) is bonded in a distorted trigonal planar geometry to one Ca(4), one Fe(4), and one C(12) atom. In the thirty-seventh O site, O(37) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(1), and one C(13) atom. In the thirty-eighth O site, O(38) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(2), and one C(14) atom. In the thirty-ninth O site, O(39) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(3), and one C(15) atom. In the fortieth O site, O(40) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(4), and one C(16) atom. In the forty-first O site, O(41) is bonded in a distorted trigonal planar geometry to one Ca(5), one Mg(1), and one C(1) atom. In the forty-second O site, O(42) is bonded in a distorted trigonal planar geometry to one Ca(6), one Mg(2), and one C(2) atom. In the forty-third O site, O(43) is bonded in a distorted trigonal planar geometry to one Ca(7), one Mg(3), and one C(3) atom. In the forty-fourth O site, O(44) is bonded in a distorted trigonal planar geometry to one Ca(8), one Mg(4), and one C(4) atom. In the forty-fifth O site, O(45) is bonded in a trigonal planar geometry to one Ca(1), one Fe(3), and one C(5) atom. In the forty-sixth O site, O(46) is bonded in a trigonal planar geometry to one Ca(2), one Fe(1), and one C(6) atom. In the forty-seventh O site, O(47) is bonded in a trigonal planar geometry to one Ca(3), one Fe(2), and one C(7) atom. In the forty-eighth O site, O(48) is bonded in a trigonal planar geometry to one Ca(4), one Fe(4), and one C(8) atom. is represented by the CIF card [CIF]
data_Ca2MgFe(CO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.887
_cell_length_b   6.115
_cell_length_c   7.840
_cell_angle_alpha   106.626
_cell_angle_beta   89.967
_cell_angle_gamma   89.817
_symmetry_Int_Tables_number   1
_cell_volume   224.465
_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  0.747  0.763  0.992  1.0
  C  C1  1  0.253  0.237  0.004  1.0
  C  C2  1  0.747  0.737  0.509  1.0
  C  C3  1  0.254  0.264  0.496  1.0
  Ca  Ca4  1  0.248  0.753  0.253  1.0
  Ca  Ca5  1  0.752  0.248  0.747  1.0
  Fe  Fe6  1  0.753  0.250  0.249  1.0
  Mg  Mg7  1  0.247  0.750  0.752  1.0
  O  O8  1  0.138  0.097  0.867  1.0
  O  O9  1  0.860  0.897  0.134  1.0
  O  O10  1  0.011  0.753  0.525  1.0
  O  O11  1  0.990  0.244  0.483  1.0
  O  O12  1  0.482  0.749  0.979  1.0
  O  O13  1  0.517  0.253  0.013  1.0
  O  O14  1  0.589  0.862  0.632  1.0
  O  O15  1  0.408  0.135  0.372  1.0
  O  O16  1  0.639  0.602  0.365  1.0
  O  O17  1  0.362  0.405  0.635  1.0
  O  O18  1  0.901  0.637  0.867  1.0
  O  O19  1  0.103  0.367  0.130  1.0
[/CIF]
.