The material described by MgFeSiO5 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(1), one O(10), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(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 Fe site, Fe(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(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(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-56°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-56°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Fe(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Fe(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(2), one Fe(1), and one Fe(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(1), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_MgFeSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.357
_cell_length_b   6.899
_cell_length_c   8.532
_cell_angle_alpha   89.897
_cell_angle_beta   37.010
_cell_angle_gamma   75.316
_symmetry_Int_Tables_number   1
_cell_volume   172.379
_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  0.505  0.230  0.667  1.0
  Mg  Mg1  1  0.510  0.730  0.316  1.0
  Fe  Fe2  1  0.499  0.486  0.996  1.0
  Fe  Fe3  1  0.499  0.986  0.995  1.0
  Si  Si4  1  0.499  0.236  0.324  1.0
  Si  Si5  1  0.496  0.736  0.669  1.0
  O  O6  1  0.276  0.108  0.328  1.0
  O  O7  1  0.727  0.365  0.103  1.0
  O  O8  1  0.717  0.868  0.664  1.0
  O  O9  1  0.266  0.611  0.893  1.0
  O  O10  1  0.858  0.569  0.362  1.0
  O  O11  1  0.143  0.896  0.714  1.0
  O  O12  1  0.140  0.401  0.632  1.0
  O  O13  1  0.855  0.074  0.275  1.0
  O  O14  1  0.494  0.737  0.084  1.0
  O  O15  1  0.502  0.236  0.909  1.0
[/CIF]
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The material described by MgFeSiO5 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(1), one O(10), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(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 Fe site, Fe(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(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(1), one O(2), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-56°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-56°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(2), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Fe(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Fe(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(2), one Fe(1), and one Fe(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(1), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_MgFeSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.357
_cell_length_b   6.899
_cell_length_c   8.532
_cell_angle_alpha   89.897
_cell_angle_beta   37.010
_cell_angle_gamma   75.316
_symmetry_Int_Tables_number   1
_cell_volume   172.379
_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  0.505  0.230  0.667  1.0
  Mg  Mg1  1  0.510  0.730  0.316  1.0
  Fe  Fe2  1  0.499  0.486  0.996  1.0
  Fe  Fe3  1  0.499  0.986  0.995  1.0
  Si  Si4  1  0.499  0.236  0.324  1.0
  Si  Si5  1  0.496  0.736  0.669  1.0
  O  O6  1  0.276  0.108  0.328  1.0
  O  O7  1  0.727  0.365  0.103  1.0
  O  O8  1  0.717  0.868  0.664  1.0
  O  O9  1  0.266  0.611  0.893  1.0
  O  O10  1  0.858  0.569  0.362  1.0
  O  O11  1  0.143  0.896  0.714  1.0
  O  O12  1  0.140  0.401  0.632  1.0
  O  O13  1  0.855  0.074  0.275  1.0
  O  O14  1  0.494  0.737  0.084  1.0
  O  O15  1  0.502  0.236  0.909  1.0
[/CIF]
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