The compound described by Sr8MgMn6O20 is Orthorhombic Perovskite-derived structured and crystallizes in the triclinic P1 space group. There are eight inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 10-coordinate geometry to one O(11), one O(12), one O(14), one O(15), one O(2), one O(3), one O(7), one O(8), and two equivalent O(18) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(12), one O(16), one O(18), one O(19), one O(7), and one O(8) atom. In the third Sr site, Sr(3) is bonded in a 10-coordinate geometry to one O(10), one O(18), one O(2), one O(20), one O(3), one O(5), one O(6), one O(9), and two equivalent O(14) atoms. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(10), one O(13), one O(14), one O(17), one O(5), one O(6), and one O(9) atom. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one O(10), one O(13), one O(4), one O(5), one O(6), one O(9), and two equivalent O(17) atoms. In the sixth Sr site, Sr(6) is bonded in a 10-coordinate geometry to one O(10), one O(14), one O(15), one O(2), one O(3), one O(5), one O(6), one O(9), and two equivalent O(20) atoms. In the seventh Sr site, Sr(7) is bonded in a 10-coordinate geometry to one O(11), one O(12), one O(18), one O(2), one O(20), one O(3), one O(7), one O(8), and two equivalent O(15) atoms. In the eighth Sr site, Sr(8) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(12), one O(19), one O(4), one O(7), one O(8), and two equivalent O(16) atoms. Mg(1) is bonded to one O(13), one O(16), one O(17), and one O(19) atom to form MgO4 tetrahedra that share  a cornercorner with one Mn(5)O6 octahedra,  a cornercorner with one Mn(6)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, and corners with two equivalent Mn(4)O6 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 30-36°. There are six inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(13), one O(17), one O(4), and one O(9) atom to form distorted MnO5 square pyramids that share corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(4)O6 trigonal bipyramids, and  an edgeedge with one Mn(5)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(10), one O(14), one O(2), one O(20), one O(3), and one O(5) atom to form a mixture of corner and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 6-11°. In the third Mn site, Mn(3) is bonded to one O(11), one O(15), one O(18), one O(2), one O(3), and one O(8) atom to form a mixture of distorted corner and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 6-11°. In the fourth Mn site, Mn(4) is bonded to one O(1), one O(12), one O(16), one O(19), one O(4), and one O(7) atom to form distorted MnO6 trigonal bipyramids that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mg(1)O4 tetrahedra, and  a faceface with one Mn(6)O6 octahedra. In the fifth Mn site, Mn(5) is bonded to one O(10), one O(17), one O(20), one O(5), one O(6), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  an edgeedge with one Mn(1)O5 square pyramid, and  a faceface with one Mn(2)O6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(11), one O(12), one O(15), one O(16), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a faceface with one Mn(3)O6 octahedra, and  a faceface with one Mn(4)O6 trigonal bipyramid. There are twenty inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(8), one Mn(1), and one Mn(4) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(3), one Sr(6), one Sr(7), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one Sr(1), one Sr(3), one Sr(6), one Sr(7), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(5), one Sr(8), one Mn(1), and one Mn(4) atom. In the fifth O site, O(5) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom to form distorted face-sharing OSr4Mn2 octahedra. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), and one Mn(5) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(4), and one Mn(6) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(3), and one Mn(6) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(1), and one Mn(5) atom. In the tenth O site, O(10) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom to form distorted face-sharing OSr4Mn2 octahedra. In the eleventh O site, O(11) is bonded in a distorted octahedral geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(3), and one Mn(6) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(4), and one Mn(6) atom. In the thirteenth O site, O(13) is bonded in a distorted rectangular see-saw-like geometry to one Sr(4), one Sr(5), one Mg(1), and one Mn(1) atom. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(4), one Sr(6), two equivalent Sr(3), and one Mn(2) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(6), two equivalent Sr(7), one Mn(3), and one Mn(6) atom. In the sixteenth O site, O(16) is bonded in a 3-coordinate geometry to one Sr(2), two equivalent Sr(8), one Mg(1), one Mn(4), and one Mn(6) atom. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Sr(4), two equivalent Sr(5), one Mg(1), one Mn(1), and one Mn(5) atom. In the eighteenth O site, O(18) is bonded in a 6-coordinate geometry to one Sr(2), one Sr(3), one Sr(7), two equivalent Sr(1), and one Mn(3) atom. In the nineteenth O site, O(19) is bonded in a distorted rectangular see-saw-like geometry to one Sr(2), one Sr(8), one Mg(1), and one Mn(4) atom. In the twentieth O site, O(20) is bonded in a 6-coordinate geometry to one Sr(3), one Sr(7), two equivalent Sr(6), one Mn(2), and one Mn(5) atom. is represented by the CIF file [CIF]
data_Sr8MgMn6O20
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.712
_cell_length_b   6.766
_cell_length_c   13.670
_cell_angle_alpha   92.274
_cell_angle_beta   86.059
_cell_angle_gamma   114.312
_symmetry_Int_Tables_number   1
_cell_volume   480.264
_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  0.248  0.478  0.127  1.0
  Sr  Sr1  1  0.778  0.503  0.936  1.0
  Sr  Sr2  1  0.724  0.487  0.359  1.0
  Sr  Sr3  1  0.200  0.508  0.550  1.0
  Sr  Sr4  1  0.887  0.916  0.598  1.0
  Sr  Sr5  1  0.012  0.062  0.352  1.0
  Sr  Sr6  1  0.536  0.054  0.142  1.0
  Sr  Sr7  1  0.529  0.937  0.890  1.0
  Mg  Mg8  1  0.123  0.743  0.749  1.0
  Mn  Mn9  1  0.640  0.262  0.670  1.0
  Mn  Mn10  1  0.360  0.755  0.345  1.0
  Mn  Mn11  1  0.878  0.745  0.156  1.0
  Mn  Mn12  1  0.150  0.257  0.835  1.0
  Mn  Mn13  1  0.452  0.017  0.498  1.0
  Mn  Mn14  1  0.042  0.005  0.004  1.0
  O  O15  1  0.476  0.281  0.790  1.0
  O  O16  1  0.148  0.780  0.251  1.0
  O  O17  1  0.628  0.767  0.253  1.0
  O  O18  1  0.897  0.167  0.742  1.0
  O  O19  1  0.128  0.788  0.454  1.0
  O  O20  1  0.299  0.206  0.523  1.0
  O  O21  1  0.383  0.207  0.994  1.0
  O  O22  1  0.135  0.775  0.042  1.0
  O  O23  1  0.775  0.219  0.537  1.0
  O  O24  1  0.590  0.789  0.461  1.0
  O  O25  1  0.675  0.790  0.028  1.0
  O  O26  1  0.931  0.219  0.958  1.0
  O  O27  1  0.850  0.568  0.664  1.0
  O  O28  1  0.200  0.452  0.347  1.0
  O  O29  1  0.021  0.072  0.143  1.0
  O  O30  1  0.050  0.926  0.860  1.0
  O  O31  1  0.391  0.932  0.644  1.0
  O  O32  1  0.744  0.442  0.161  1.0
  O  O33  1  0.224  0.558  0.830  1.0
  O  O34  1  0.527  0.083  0.359  1.0
[/CIF]
.
The compound described by Sr8MgMn6O20 is Orthorhombic Perovskite-derived structured and crystallizes in the triclinic P1 space group. There are eight inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 10-coordinate geometry to one O(11), one O(12), one O(14), one O(15), one O(2), one O(3), one O(7), one O(8), and two equivalent O(18) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(12), one O(16), one O(18), one O(19), one O(7), and one O(8) atom. In the third Sr site, Sr(3) is bonded in a 10-coordinate geometry to one O(10), one O(18), one O(2), one O(20), one O(3), one O(5), one O(6), one O(9), and two equivalent O(14) atoms. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(10), one O(13), one O(14), one O(17), one O(5), one O(6), and one O(9) atom. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one O(10), one O(13), one O(4), one O(5), one O(6), one O(9), and two equivalent O(17) atoms. In the sixth Sr site, Sr(6) is bonded in a 10-coordinate geometry to one O(10), one O(14), one O(15), one O(2), one O(3), one O(5), one O(6), one O(9), and two equivalent O(20) atoms. In the seventh Sr site, Sr(7) is bonded in a 10-coordinate geometry to one O(11), one O(12), one O(18), one O(2), one O(20), one O(3), one O(7), one O(8), and two equivalent O(15) atoms. In the eighth Sr site, Sr(8) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(12), one O(19), one O(4), one O(7), one O(8), and two equivalent O(16) atoms. Mg(1) is bonded to one O(13), one O(16), one O(17), and one O(19) atom to form MgO4 tetrahedra that share  a cornercorner with one Mn(5)O6 octahedra,  a cornercorner with one Mn(6)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, and corners with two equivalent Mn(4)O6 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 30-36°. There are six inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(13), one O(17), one O(4), and one O(9) atom to form distorted MnO5 square pyramids that share corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Mn(4)O6 trigonal bipyramids, and  an edgeedge with one Mn(5)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(10), one O(14), one O(2), one O(20), one O(3), and one O(5) atom to form a mixture of corner and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 6-11°. In the third Mn site, Mn(3) is bonded to one O(11), one O(15), one O(18), one O(2), one O(3), and one O(8) atom to form a mixture of distorted corner and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 6-11°. In the fourth Mn site, Mn(4) is bonded to one O(1), one O(12), one O(16), one O(19), one O(4), and one O(7) atom to form distorted MnO6 trigonal bipyramids that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mg(1)O4 tetrahedra, and  a faceface with one Mn(6)O6 octahedra. In the fifth Mn site, Mn(5) is bonded to one O(10), one O(17), one O(20), one O(5), one O(6), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  an edgeedge with one Mn(1)O5 square pyramid, and  a faceface with one Mn(2)O6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(11), one O(12), one O(15), one O(16), one O(7), and one O(8) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a faceface with one Mn(3)O6 octahedra, and  a faceface with one Mn(4)O6 trigonal bipyramid. There are twenty inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(8), one Mn(1), and one Mn(4) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(3), one Sr(6), one Sr(7), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one Sr(1), one Sr(3), one Sr(6), one Sr(7), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(5), one Sr(8), one Mn(1), and one Mn(4) atom. In the fifth O site, O(5) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom to form distorted face-sharing OSr4Mn2 octahedra. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), and one Mn(5) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(4), and one Mn(6) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(3), and one Mn(6) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(1), and one Mn(5) atom. In the tenth O site, O(10) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom to form distorted face-sharing OSr4Mn2 octahedra. In the eleventh O site, O(11) is bonded in a distorted octahedral geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(3), and one Mn(6) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Sr(7), one Sr(8), one Mn(4), and one Mn(6) atom. In the thirteenth O site, O(13) is bonded in a distorted rectangular see-saw-like geometry to one Sr(4), one Sr(5), one Mg(1), and one Mn(1) atom. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(4), one Sr(6), two equivalent Sr(3), and one Mn(2) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(6), two equivalent Sr(7), one Mn(3), and one Mn(6) atom. In the sixteenth O site, O(16) is bonded in a 3-coordinate geometry to one Sr(2), two equivalent Sr(8), one Mg(1), one Mn(4), and one Mn(6) atom. In the seventeenth O site, O(17) is bonded in a 3-coordinate geometry to one Sr(4), two equivalent Sr(5), one Mg(1), one Mn(1), and one Mn(5) atom. In the eighteenth O site, O(18) is bonded in a 6-coordinate geometry to one Sr(2), one Sr(3), one Sr(7), two equivalent Sr(1), and one Mn(3) atom. In the nineteenth O site, O(19) is bonded in a distorted rectangular see-saw-like geometry to one Sr(2), one Sr(8), one Mg(1), and one Mn(4) atom. In the twentieth O site, O(20) is bonded in a 6-coordinate geometry to one Sr(3), one Sr(7), two equivalent Sr(6), one Mn(2), and one Mn(5) atom. is represented by the CIF file [CIF]
data_Sr8MgMn6O20
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.712
_cell_length_b   6.766
_cell_length_c   13.670
_cell_angle_alpha   92.274
_cell_angle_beta   86.059
_cell_angle_gamma   114.312
_symmetry_Int_Tables_number   1
_cell_volume   480.264
_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  0.248  0.478  0.127  1.0
  Sr  Sr1  1  0.778  0.503  0.936  1.0
  Sr  Sr2  1  0.724  0.487  0.359  1.0
  Sr  Sr3  1  0.200  0.508  0.550  1.0
  Sr  Sr4  1  0.887  0.916  0.598  1.0
  Sr  Sr5  1  0.012  0.062  0.352  1.0
  Sr  Sr6  1  0.536  0.054  0.142  1.0
  Sr  Sr7  1  0.529  0.937  0.890  1.0
  Mg  Mg8  1  0.123  0.743  0.749  1.0
  Mn  Mn9  1  0.640  0.262  0.670  1.0
  Mn  Mn10  1  0.360  0.755  0.345  1.0
  Mn  Mn11  1  0.878  0.745  0.156  1.0
  Mn  Mn12  1  0.150  0.257  0.835  1.0
  Mn  Mn13  1  0.452  0.017  0.498  1.0
  Mn  Mn14  1  0.042  0.005  0.004  1.0
  O  O15  1  0.476  0.281  0.790  1.0
  O  O16  1  0.148  0.780  0.251  1.0
  O  O17  1  0.628  0.767  0.253  1.0
  O  O18  1  0.897  0.167  0.742  1.0
  O  O19  1  0.128  0.788  0.454  1.0
  O  O20  1  0.299  0.206  0.523  1.0
  O  O21  1  0.383  0.207  0.994  1.0
  O  O22  1  0.135  0.775  0.042  1.0
  O  O23  1  0.775  0.219  0.537  1.0
  O  O24  1  0.590  0.789  0.461  1.0
  O  O25  1  0.675  0.790  0.028  1.0
  O  O26  1  0.931  0.219  0.958  1.0
  O  O27  1  0.850  0.568  0.664  1.0
  O  O28  1  0.200  0.452  0.347  1.0
  O  O29  1  0.021  0.072  0.143  1.0
  O  O30  1  0.050  0.926  0.860  1.0
  O  O31  1  0.391  0.932  0.644  1.0
  O  O32  1  0.744  0.442  0.161  1.0
  O  O33  1  0.224  0.558  0.830  1.0
  O  O34  1  0.527  0.083  0.359  1.0
[/CIF]
.