The compound described by SrMgMn(PO4)2 crystallizes in the triclinic P-1 space group. Sr(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(8), two equivalent O(1), and two equivalent O(6) atoms. Mg(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(4), one O(5), and one O(7) atom. Mn(1) is bonded to one O(3), one O(4), one O(5), one O(7), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and  an edgeedge with one P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-63°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-61°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Sr(1), one Mg(1), and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one Mg(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Mn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(1), one Mg(1), one Mn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Sr(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), two equivalent Mn(1), and one P(2) atom. is represented by the CIF file [CIF]
data_SrMgMn(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.565
_cell_length_b   6.989
_cell_length_c   9.499
_cell_angle_alpha   110.890
_cell_angle_beta   101.492
_cell_angle_gamma   97.924
_symmetry_Int_Tables_number   1
_cell_volume   329.337
_cell_formula_units_Z   2
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
  Mg  Mg0  1  0.993  0.385  0.654  1.0
  Mg  Mg1  1  0.007  0.615  0.346  1.0
  Mn  Mn2  1  0.630  0.837  0.559  1.0
  Mn  Mn3  1  0.370  0.163  0.441  1.0
  O  O4  1  0.819  0.546  0.891  1.0
  O  O5  1  0.181  0.454  0.109  1.0
  O  O6  1  0.657  0.473  0.210  1.0
  O  O7  1  0.343  0.527  0.790  1.0
  O  O8  1  0.673  0.805  0.778  1.0
  O  O9  1  0.327  0.195  0.222  1.0
  O  O10  1  0.962  0.119  0.696  1.0
  O  O11  1  0.038  0.881  0.304  1.0
  O  O12  1  0.013  0.751  0.576  1.0
  O  O13  1  0.987  0.249  0.424  1.0
  O  O14  1  0.257  0.993  0.866  1.0
  O  O15  1  0.743  0.007  0.134  1.0
  O  O16  1  0.364  0.575  0.391  1.0
  O  O17  1  0.636  0.425  0.609  1.0
  O  O18  1  0.615  0.947  0.360  1.0
  O  O19  1  0.385  0.053  0.640  1.0
  P  P20  1  0.387  0.420  0.228  1.0
  P  P21  1  0.613  0.580  0.772  1.0
  P  P22  1  0.840  0.022  0.301  1.0
  P  P23  1  0.160  0.978  0.699  1.0
  Sr  Sr24  1  0.249  0.802  0.049  1.0
  Sr  Sr25  1  0.751  0.198  0.951  1.0
[/CIF]
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The compound described by SrMgMn(PO4)2 crystallizes in the triclinic P-1 space group. Sr(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(8), two equivalent O(1), and two equivalent O(6) atoms. Mg(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(4), one O(5), and one O(7) atom. Mn(1) is bonded to one O(3), one O(4), one O(5), one O(7), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and  an edgeedge with one P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-63°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-61°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Sr(1), one Mg(1), and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one Mg(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Mn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(1), one Mg(1), one Mn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Sr(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), two equivalent Mn(1), and one P(2) atom. is represented by the CIF file [CIF]
data_SrMgMn(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.565
_cell_length_b   6.989
_cell_length_c   9.499
_cell_angle_alpha   110.890
_cell_angle_beta   101.492
_cell_angle_gamma   97.924
_symmetry_Int_Tables_number   1
_cell_volume   329.337
_cell_formula_units_Z   2
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
  Mg  Mg0  1  0.993  0.385  0.654  1.0
  Mg  Mg1  1  0.007  0.615  0.346  1.0
  Mn  Mn2  1  0.630  0.837  0.559  1.0
  Mn  Mn3  1  0.370  0.163  0.441  1.0
  O  O4  1  0.819  0.546  0.891  1.0
  O  O5  1  0.181  0.454  0.109  1.0
  O  O6  1  0.657  0.473  0.210  1.0
  O  O7  1  0.343  0.527  0.790  1.0
  O  O8  1  0.673  0.805  0.778  1.0
  O  O9  1  0.327  0.195  0.222  1.0
  O  O10  1  0.962  0.119  0.696  1.0
  O  O11  1  0.038  0.881  0.304  1.0
  O  O12  1  0.013  0.751  0.576  1.0
  O  O13  1  0.987  0.249  0.424  1.0
  O  O14  1  0.257  0.993  0.866  1.0
  O  O15  1  0.743  0.007  0.134  1.0
  O  O16  1  0.364  0.575  0.391  1.0
  O  O17  1  0.636  0.425  0.609  1.0
  O  O18  1  0.615  0.947  0.360  1.0
  O  O19  1  0.385  0.053  0.640  1.0
  P  P20  1  0.387  0.420  0.228  1.0
  P  P21  1  0.613  0.580  0.772  1.0
  P  P22  1  0.840  0.022  0.301  1.0
  P  P23  1  0.160  0.978  0.699  1.0
  Sr  Sr24  1  0.249  0.802  0.049  1.0
  Sr  Sr25  1  0.751  0.198  0.951  1.0
[/CIF]
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