The material described by Sr3MgMn4O12 crystallizes in the triclinic P1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(8), and two equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one O(10), one O(12), one O(6), one O(8), and one O(9) atom. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(12), one O(7), one O(9), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. Mg(1) is bonded to one O(1), one O(10), one O(3), one O(7), and one O(8) atom to form MgO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra,  an edgeedge with one Mn(4)O6 octahedra,  a faceface with one Mn(2)O6 octahedra, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(12), one O(2), one O(4), one O(5), one O(6), and one O(9) atom to form a mixture of distorted corner and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 21-26°. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form MnO6 octahedra that share corners with three equivalent Mn(3)O6 octahedra,  a faceface with one Mn(1)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 25-29°. In the third Mn site, Mn(3) is bonded to one O(1), one O(10), one O(11), one O(3), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mn(2)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids,  a faceface with one Mn(4)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 25-29°. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(11), one O(12), one O(6), one O(8), and one O(9) atom to form MnO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra,  an edgeedge with one Mg(1)O5 square pyramid, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 21-26°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(3), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a distorted L-shaped geometry to one Sr(1), two equivalent Sr(3), one Mn(1), and one Mn(2) atom. In the fifth O site, O(5) is bonded in a distorted L-shaped geometry to one Sr(1), two equivalent Sr(3), one Mn(1), and one Mn(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Mn(1), and one Mn(4) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Sr(3), two equivalent Sr(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Sr(1), one Sr(2), one Mg(1), one Mn(3), and one Mn(4) atom. In the ninth O site, O(9) is bonded in a rectangular see-saw-like geometry to one Sr(2), one Sr(3), one Mn(1), and one Mn(4) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(1), one Sr(2), one Mg(1), one Mn(3), and one Mn(4) atom. In the eleventh O site, O(11) is bonded in a distorted L-shaped geometry to one Mn(3) and one Mn(4) atom. In the twelfth O site, O(12) is bonded in a rectangular see-saw-like geometry to one Sr(2), one Sr(3), one Mn(1), and one Mn(4) atom. is represented by the CIF file [CIF]
data_Sr3MgMn4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.670
_cell_length_b   5.672
_cell_length_c   9.565
_cell_angle_alpha   91.719
_cell_angle_beta   88.307
_cell_angle_gamma   121.065
_symmetry_Int_Tables_number   1
_cell_volume   263.328
_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
  Sr  Sr0  1  0.026  0.974  0.538  1.0
  Sr  Sr1  1  0.244  0.757  0.184  1.0
  Sr  Sr2  1  0.670  0.331  0.772  1.0
  Mg  Mg3  1  0.452  0.548  0.368  1.0
  Mn  Mn4  1  0.327  0.674  0.889  1.0
  Mn  Mn5  1  0.358  0.642  0.620  1.0
  Mn  Mn6  1  0.711  0.290  0.383  1.0
  Mn  Mn7  1  0.643  0.358  0.102  1.0
  O  O8  1  0.081  0.439  0.464  1.0
  O  O9  1  0.195  0.804  0.720  1.0
  O  O10  1  0.559  0.919  0.463  1.0
  O  O11  1  0.185  0.367  0.756  1.0
  O  O12  1  0.634  0.817  0.755  1.0
  O  O13  1  0.457  0.546  0.031  1.0
  O  O14  1  0.560  0.440  0.539  1.0
  O  O15  1  0.373  0.194  0.282  1.0
  O  O16  1  0.447  0.045  0.982  1.0
  O  O17  1  0.808  0.629  0.283  1.0
  O  O18  1  0.805  0.196  0.210  1.0
  O  O19  1  0.956  0.553  0.982  1.0
[/CIF]
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The material described by Sr3MgMn4O12 crystallizes in the triclinic P1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(8), and two equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one O(10), one O(12), one O(6), one O(8), and one O(9) atom. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(12), one O(7), one O(9), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. Mg(1) is bonded to one O(1), one O(10), one O(3), one O(7), and one O(8) atom to form MgO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra,  an edgeedge with one Mn(4)O6 octahedra,  a faceface with one Mn(2)O6 octahedra, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(12), one O(2), one O(4), one O(5), one O(6), and one O(9) atom to form a mixture of distorted corner and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 21-26°. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form MnO6 octahedra that share corners with three equivalent Mn(3)O6 octahedra,  a faceface with one Mn(1)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 25-29°. In the third Mn site, Mn(3) is bonded to one O(1), one O(10), one O(11), one O(3), one O(7), and one O(8) atom to form MnO6 octahedra that share corners with three equivalent Mn(2)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids,  a faceface with one Mn(4)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 25-29°. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(11), one O(12), one O(6), one O(8), and one O(9) atom to form MnO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra,  an edgeedge with one Mg(1)O5 square pyramid, and  a faceface with one Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 21-26°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(3), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a distorted L-shaped geometry to one Sr(1), two equivalent Sr(3), one Mn(1), and one Mn(2) atom. In the fifth O site, O(5) is bonded in a distorted L-shaped geometry to one Sr(1), two equivalent Sr(3), one Mn(1), and one Mn(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Mn(1), and one Mn(4) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Sr(3), two equivalent Sr(1), one Mg(1), one Mn(2), and one Mn(3) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Sr(1), one Sr(2), one Mg(1), one Mn(3), and one Mn(4) atom. In the ninth O site, O(9) is bonded in a rectangular see-saw-like geometry to one Sr(2), one Sr(3), one Mn(1), and one Mn(4) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(1), one Sr(2), one Mg(1), one Mn(3), and one Mn(4) atom. In the eleventh O site, O(11) is bonded in a distorted L-shaped geometry to one Mn(3) and one Mn(4) atom. In the twelfth O site, O(12) is bonded in a rectangular see-saw-like geometry to one Sr(2), one Sr(3), one Mn(1), and one Mn(4) atom. is represented by the CIF file [CIF]
data_Sr3MgMn4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.670
_cell_length_b   5.672
_cell_length_c   9.565
_cell_angle_alpha   91.719
_cell_angle_beta   88.307
_cell_angle_gamma   121.065
_symmetry_Int_Tables_number   1
_cell_volume   263.328
_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
  Sr  Sr0  1  0.026  0.974  0.538  1.0
  Sr  Sr1  1  0.244  0.757  0.184  1.0
  Sr  Sr2  1  0.670  0.331  0.772  1.0
  Mg  Mg3  1  0.452  0.548  0.368  1.0
  Mn  Mn4  1  0.327  0.674  0.889  1.0
  Mn  Mn5  1  0.358  0.642  0.620  1.0
  Mn  Mn6  1  0.711  0.290  0.383  1.0
  Mn  Mn7  1  0.643  0.358  0.102  1.0
  O  O8  1  0.081  0.439  0.464  1.0
  O  O9  1  0.195  0.804  0.720  1.0
  O  O10  1  0.559  0.919  0.463  1.0
  O  O11  1  0.185  0.367  0.756  1.0
  O  O12  1  0.634  0.817  0.755  1.0
  O  O13  1  0.457  0.546  0.031  1.0
  O  O14  1  0.560  0.440  0.539  1.0
  O  O15  1  0.373  0.194  0.282  1.0
  O  O16  1  0.447  0.045  0.982  1.0
  O  O17  1  0.808  0.629  0.283  1.0
  O  O18  1  0.805  0.196  0.210  1.0
  O  O19  1  0.956  0.553  0.982  1.0
[/CIF]
.