The compound described by MgMnSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one O(8) atom to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(9) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(10), one O(3), one O(4), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-57°. In the second Si site, Si(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-57°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mg(2), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mn(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mn(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mn(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), one Mn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Mg(2), one Mn(2), and one Si(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Mn(1), and one Si(2) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(2), and one Si(1) atom. In the tenth O site, O(10) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_MgMnSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.232
_cell_length_b   6.932
_cell_length_c   5.254
_cell_angle_alpha   74.921
_cell_angle_beta   105.054
_cell_angle_gamma   75.659
_symmetry_Int_Tables_number   1
_cell_volume   167.199
_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  0.333  0.236  0.172  1.0
  Mg  Mg1  1  0.669  0.746  0.831  1.0
  Mn  Mn2  1  1.000  0.994  0.500  1.0
  Mn  Mn3  1  0.999  0.494  0.500  1.0
  Si  Si4  1  0.680  0.243  0.820  1.0
  Si  Si5  1  0.318  0.744  0.180  1.0
  O  O6  1  0.911  0.743  0.589  1.0
  O  O7  1  0.088  0.245  0.411  1.0
  O  O8  1  0.675  0.116  0.595  1.0
  O  O9  1  0.917  0.362  0.830  1.0
  O  O10  1  0.325  0.871  0.406  1.0
  O  O11  1  0.081  0.626  0.171  1.0
  O  O12  1  0.625  0.573  0.238  1.0
  O  O13  1  0.270  0.910  0.871  1.0
  O  O14  1  0.374  0.415  0.762  1.0
  O  O15  1  0.729  0.077  0.130  1.0
[/CIF]
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The compound described by MgMnSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one O(8) atom to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(9) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(10), one O(3), one O(4), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-57°. In the second Si site, Si(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-57°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mg(2), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mn(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mn(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Mn(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), one Mn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Mg(2), one Mn(2), and one Si(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Mn(1), and one Si(2) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(2), and one Si(1) atom. In the tenth O site, O(10) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_MgMnSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.232
_cell_length_b   6.932
_cell_length_c   5.254
_cell_angle_alpha   74.921
_cell_angle_beta   105.054
_cell_angle_gamma   75.659
_symmetry_Int_Tables_number   1
_cell_volume   167.199
_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  0.333  0.236  0.172  1.0
  Mg  Mg1  1  0.669  0.746  0.831  1.0
  Mn  Mn2  1  1.000  0.994  0.500  1.0
  Mn  Mn3  1  0.999  0.494  0.500  1.0
  Si  Si4  1  0.680  0.243  0.820  1.0
  Si  Si5  1  0.318  0.744  0.180  1.0
  O  O6  1  0.911  0.743  0.589  1.0
  O  O7  1  0.088  0.245  0.411  1.0
  O  O8  1  0.675  0.116  0.595  1.0
  O  O9  1  0.917  0.362  0.830  1.0
  O  O10  1  0.325  0.871  0.406  1.0
  O  O11  1  0.081  0.626  0.171  1.0
  O  O12  1  0.625  0.573  0.238  1.0
  O  O13  1  0.270  0.910  0.871  1.0
  O  O14  1  0.374  0.415  0.762  1.0
  O  O15  1  0.729  0.077  0.130  1.0
[/CIF]
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