The structure 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 9-coordinate geometry to one O(11), one O(12), one O(14), one O(15), one O(2), one O(3), one O(8), and two equivalent O(18) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(1), one O(13), one O(16), one O(4), one O(7), and two equivalent O(19) atoms. 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 10-coordinate geometry to one O(1), one O(10), one O(17), one O(19), one O(4), one O(5), one O(6), one O(9), and two equivalent O(13) atoms. In the fifth Sr site, Sr(5) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(13), one O(16), 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 9-coordinate geometry to one O(11), one O(12), one O(18), one O(2), one O(20), one O(3), one O(8), and two equivalent O(15) atoms. In the eighth Sr site, Sr(8) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(17), one O(19), one O(4), one O(7), and two equivalent O(16) atoms. Mg(1) is bonded in a 5-coordinate geometry to one O(11), one O(12), one O(18), one O(7), and one O(8) atom. 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), one O(6), and one O(9) atom to form a mixture of face and corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. 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 face and corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 13-18°. 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 corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 13-18°. 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 corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. 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 face-sharing MnO6 octahedra. In the sixth Mn site, Mn(6) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(15), one O(16), one O(7), and one O(8) atom. There are twenty inequivalent O sites. In the first O site, O(1) is bonded to one Sr(2), one Sr(4), one Sr(5), one Sr(8), one Mn(1), and one Mn(4) atom to form a mixture of distorted face and corner-sharing OSr4Mn2 octahedra. In the second O site, O(2) is bonded in a 2-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 2-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 fourth O site, O(4) is bonded in a 2-coordinate geometry to one Sr(2), one Sr(4), one Sr(5), one Sr(8), one Mn(1), and one Mn(4) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom. In the sixth O site, O(6) is bonded in a 6-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 seventh O site, O(7) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(8), one Mg(1), one Mn(4), and one Mn(6) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(7), one Mg(1), one Mn(3), and one Mn(6) atom. In the ninth O site, O(9) is bonded in a 6-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 in a 6-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom. In the eleventh O site, O(11) is bonded to one Sr(1), one Sr(7), one Mg(1), one Mn(3), and one Mn(6) atom to form distorted corner-sharing OSr2MgMn2 square pyramids. The corner-sharing octahedral tilt angles are 57°. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Sr(1), one Sr(7), one Sr(8), one Mg(1), one Mn(4), and one Mn(6) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(5), two equivalent Sr(4), and one Mn(1) atom. In the fourteenth O site, O(14) is bonded in a 5-coordinate geometry to one Sr(1), 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 5-coordinate geometry to one Sr(2), one Sr(5), two equivalent Sr(8), one Mn(4), and one Mn(6) atom. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Sr(4), one Sr(8), two equivalent Sr(5), 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(3), one Sr(7), two equivalent Sr(1), one Mg(1), and one Mn(3) atom. In the nineteenth O site, O(19) is bonded to one Sr(4), one Sr(8), two equivalent Sr(2), and one Mn(4) atom to form distorted OSr4Mn trigonal bipyramids that share corners with two equivalent O(1)Sr4Mn2 octahedra, corners with two equivalent O(19)Sr4Mn trigonal bipyramids, and  a faceface with one O(1)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 58-64°. In the twentieth O site, O(20) is bonded to one Sr(3), one Sr(7), two equivalent Sr(6), one Mn(2), and one Mn(5) atom to form distorted OSr4Mn2 octahedra that share corners with two equivalent O(20)Sr4Mn2 octahedra and  a cornercorner with one O(11)Sr2MgMn2 square pyramid. The corner-sharing octahedral tilt angles are 5°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr8MgMn6O20
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.559
_cell_length_b   6.807
_cell_length_c   13.748
_cell_angle_alpha   90.590
_cell_angle_beta   90.819
_cell_angle_gamma   114.529
_symmetry_Int_Tables_number   1
_cell_volume   473.162
_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  0.209  0.456  0.148  1.0
  Sr  Sr1  1  0.763  0.563  0.819  1.0
  Sr  Sr2  1  0.732  0.471  0.393  1.0
  Sr  Sr3  1  0.263  0.528  0.614  1.0
  Sr  Sr4  1  0.978  0.956  0.630  1.0
  Sr  Sr5  1  0.034  0.057  0.367  1.0
  Sr  Sr6  1  0.519  0.025  0.158  1.0
  Sr  Sr7  1  0.474  0.978  0.858  1.0
  Mg  Mg8  1  0.710  0.446  0.024  1.0
  Mn  Mn9  1  0.625  0.255  0.645  1.0
  Mn  Mn10  1  0.371  0.735  0.351  1.0
  Mn  Mn11  1  0.859  0.737  0.165  1.0
  Mn  Mn12  1  0.139  0.289  0.842  1.0
  Mn  Mn13  1  0.504  0.999  0.496  1.0
  Mn  Mn14  1  0.975  0.996  0.007  1.0
  O  O15  1  0.359  0.241  0.729  1.0
  O  O16  1  0.150  0.758  0.250  1.0
  O  O17  1  0.660  0.771  0.269  1.0
  O  O18  1  0.839  0.228  0.750  1.0
  O  O19  1  0.161  0.775  0.456  1.0
  O  O20  1  0.385  0.218  0.530  1.0
  O  O21  1  0.408  0.300  0.938  1.0
  O  O22  1  0.059  0.739  0.045  1.0
  O  O23  1  0.848  0.216  0.534  1.0
  O  O24  1  0.617  0.776  0.463  1.0
  O  O25  1  0.605  0.727  0.069  1.0
  O  O26  1  0.847  0.218  0.992  1.0
  O  O27  1  0.784  0.560  0.644  1.0
  O  O28  1  0.225  0.439  0.342  1.0
  O  O29  1  0.035  0.055  0.149  1.0
  O  O30  1  0.967  0.955  0.867  1.0
  O  O31  1  0.463  0.931  0.632  1.0
  O  O32  1  0.702  0.426  0.168  1.0
  O  O33  1  0.275  0.589  0.816  1.0
  O  O34  1  0.539  0.069  0.360  1.0
[/CIF]
.
The structure 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 9-coordinate geometry to one O(11), one O(12), one O(14), one O(15), one O(2), one O(3), one O(8), and two equivalent O(18) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(1), one O(13), one O(16), one O(4), one O(7), and two equivalent O(19) atoms. 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 10-coordinate geometry to one O(1), one O(10), one O(17), one O(19), one O(4), one O(5), one O(6), one O(9), and two equivalent O(13) atoms. In the fifth Sr site, Sr(5) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(13), one O(16), 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 9-coordinate geometry to one O(11), one O(12), one O(18), one O(2), one O(20), one O(3), one O(8), and two equivalent O(15) atoms. In the eighth Sr site, Sr(8) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(17), one O(19), one O(4), one O(7), and two equivalent O(16) atoms. Mg(1) is bonded in a 5-coordinate geometry to one O(11), one O(12), one O(18), one O(7), and one O(8) atom. 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), one O(6), and one O(9) atom to form a mixture of face and corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. 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 face and corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 13-18°. 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 corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 13-18°. 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 corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. 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 face-sharing MnO6 octahedra. In the sixth Mn site, Mn(6) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(15), one O(16), one O(7), and one O(8) atom. There are twenty inequivalent O sites. In the first O site, O(1) is bonded to one Sr(2), one Sr(4), one Sr(5), one Sr(8), one Mn(1), and one Mn(4) atom to form a mixture of distorted face and corner-sharing OSr4Mn2 octahedra. In the second O site, O(2) is bonded in a 2-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 2-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 fourth O site, O(4) is bonded in a 2-coordinate geometry to one Sr(2), one Sr(4), one Sr(5), one Sr(8), one Mn(1), and one Mn(4) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom. In the sixth O site, O(6) is bonded in a 6-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 seventh O site, O(7) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(8), one Mg(1), one Mn(4), and one Mn(6) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(7), one Mg(1), one Mn(3), and one Mn(6) atom. In the ninth O site, O(9) is bonded in a 6-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 in a 6-coordinate geometry to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Mn(2), and one Mn(5) atom. In the eleventh O site, O(11) is bonded to one Sr(1), one Sr(7), one Mg(1), one Mn(3), and one Mn(6) atom to form distorted corner-sharing OSr2MgMn2 square pyramids. The corner-sharing octahedral tilt angles are 57°. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Sr(1), one Sr(7), one Sr(8), one Mg(1), one Mn(4), and one Mn(6) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(5), two equivalent Sr(4), and one Mn(1) atom. In the fourteenth O site, O(14) is bonded in a 5-coordinate geometry to one Sr(1), 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 5-coordinate geometry to one Sr(2), one Sr(5), two equivalent Sr(8), one Mn(4), and one Mn(6) atom. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Sr(4), one Sr(8), two equivalent Sr(5), 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(3), one Sr(7), two equivalent Sr(1), one Mg(1), and one Mn(3) atom. In the nineteenth O site, O(19) is bonded to one Sr(4), one Sr(8), two equivalent Sr(2), and one Mn(4) atom to form distorted OSr4Mn trigonal bipyramids that share corners with two equivalent O(1)Sr4Mn2 octahedra, corners with two equivalent O(19)Sr4Mn trigonal bipyramids, and  a faceface with one O(1)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 58-64°. In the twentieth O site, O(20) is bonded to one Sr(3), one Sr(7), two equivalent Sr(6), one Mn(2), and one Mn(5) atom to form distorted OSr4Mn2 octahedra that share corners with two equivalent O(20)Sr4Mn2 octahedra and  a cornercorner with one O(11)Sr2MgMn2 square pyramid. The corner-sharing octahedral tilt angles are 5°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr8MgMn6O20
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.559
_cell_length_b   6.807
_cell_length_c   13.748
_cell_angle_alpha   90.590
_cell_angle_beta   90.819
_cell_angle_gamma   114.529
_symmetry_Int_Tables_number   1
_cell_volume   473.162
_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  0.209  0.456  0.148  1.0
  Sr  Sr1  1  0.763  0.563  0.819  1.0
  Sr  Sr2  1  0.732  0.471  0.393  1.0
  Sr  Sr3  1  0.263  0.528  0.614  1.0
  Sr  Sr4  1  0.978  0.956  0.630  1.0
  Sr  Sr5  1  0.034  0.057  0.367  1.0
  Sr  Sr6  1  0.519  0.025  0.158  1.0
  Sr  Sr7  1  0.474  0.978  0.858  1.0
  Mg  Mg8  1  0.710  0.446  0.024  1.0
  Mn  Mn9  1  0.625  0.255  0.645  1.0
  Mn  Mn10  1  0.371  0.735  0.351  1.0
  Mn  Mn11  1  0.859  0.737  0.165  1.0
  Mn  Mn12  1  0.139  0.289  0.842  1.0
  Mn  Mn13  1  0.504  0.999  0.496  1.0
  Mn  Mn14  1  0.975  0.996  0.007  1.0
  O  O15  1  0.359  0.241  0.729  1.0
  O  O16  1  0.150  0.758  0.250  1.0
  O  O17  1  0.660  0.771  0.269  1.0
  O  O18  1  0.839  0.228  0.750  1.0
  O  O19  1  0.161  0.775  0.456  1.0
  O  O20  1  0.385  0.218  0.530  1.0
  O  O21  1  0.408  0.300  0.938  1.0
  O  O22  1  0.059  0.739  0.045  1.0
  O  O23  1  0.848  0.216  0.534  1.0
  O  O24  1  0.617  0.776  0.463  1.0
  O  O25  1  0.605  0.727  0.069  1.0
  O  O26  1  0.847  0.218  0.992  1.0
  O  O27  1  0.784  0.560  0.644  1.0
  O  O28  1  0.225  0.439  0.342  1.0
  O  O29  1  0.035  0.055  0.149  1.0
  O  O30  1  0.967  0.955  0.867  1.0
  O  O31  1  0.463  0.931  0.632  1.0
  O  O32  1  0.702  0.426  0.168  1.0
  O  O33  1  0.275  0.589  0.816  1.0
  O  O34  1  0.539  0.069  0.360  1.0
[/CIF]
.