The crystal structure described by MgFe2Zn2(SiO5)2 crystallizes in the triclinic P1 space group. Mg(1) 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 MgO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and faces with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. 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 Mg(1)O6 octahedra, 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 range from 46-48°. 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, corners with two equivalent Si(2)O4 tetrahedra, and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(4), one O(7), and one O(8) atom. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(2), one O(4), one O(5), one O(6), and one O(9) atom. 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 Mg(1)O6 octahedra, 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 25-54°. 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 Mg(1)O6 octahedra, 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 25-54°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Zn(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Zn(1), one Zn(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Fe(1), one Zn(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a T-shaped geometry to one Fe(1), one Zn(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Zn(1), and one Si(1) atom. In the ninth O site, O(9) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Zn(2) atom to form distorted corner-sharing OMgZnFe2 trigonal pyramids. In the tenth O site, O(10) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Zn(1) atom to form distorted corner-sharing OMgZnFe2 trigonal pyramids. is represented by the CIF file [CIF]
data_MgZn2Fe2(SiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.465
_cell_length_b   7.226
_cell_length_c   7.933
_cell_angle_alpha   90.122
_cell_angle_beta   42.930
_cell_angle_gamma   73.166
_symmetry_Int_Tables_number   1
_cell_volume   192.901
_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
  Mg  Mg0  1  1.000  0.986  0.496  1.0
  Zn  Zn1  1  0.286  0.301  0.788  1.0
  Zn  Zn2  1  0.713  0.669  0.203  1.0
  Fe  Fe3  1  0.499  0.486  0.996  1.0
  Fe  Fe4  1  0.500  0.986  0.996  1.0
  Si  Si5  1  0.526  0.238  0.341  1.0
  Si  Si6  1  0.472  0.734  0.652  1.0
  O  O7  1  0.470  0.065  0.251  1.0
  O  O8  1  0.687  0.376  0.140  1.0
  O  O9  1  0.528  0.907  0.742  1.0
  O  O10  1  0.312  0.595  0.852  1.0
  O  O11  1  0.898  0.586  0.344  1.0
  O  O12  1  0.167  0.837  0.646  1.0
  O  O13  1  0.100  0.386  0.648  1.0
  O  O14  1  0.831  0.135  0.347  1.0
  O  O15  1  0.444  0.755  0.123  1.0
  O  O16  1  0.555  0.217  0.869  1.0
[/CIF]
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The crystal structure described by MgFe2Zn2(SiO5)2 crystallizes in the triclinic P1 space group. Mg(1) 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 MgO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and faces with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. 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 Mg(1)O6 octahedra, 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 range from 46-48°. 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, corners with two equivalent Si(2)O4 tetrahedra, and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(4), one O(7), and one O(8) atom. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(2), one O(4), one O(5), one O(6), and one O(9) atom. 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 Mg(1)O6 octahedra, 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 25-54°. 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 Mg(1)O6 octahedra, 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 25-54°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Zn(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Zn(1), one Zn(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Fe(1), one Zn(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a T-shaped geometry to one Fe(1), one Zn(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Zn(1), and one Si(1) atom. In the ninth O site, O(9) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Zn(2) atom to form distorted corner-sharing OMgZnFe2 trigonal pyramids. In the tenth O site, O(10) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Zn(1) atom to form distorted corner-sharing OMgZnFe2 trigonal pyramids. is represented by the CIF file [CIF]
data_MgZn2Fe2(SiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.465
_cell_length_b   7.226
_cell_length_c   7.933
_cell_angle_alpha   90.122
_cell_angle_beta   42.930
_cell_angle_gamma   73.166
_symmetry_Int_Tables_number   1
_cell_volume   192.901
_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
  Mg  Mg0  1  1.000  0.986  0.496  1.0
  Zn  Zn1  1  0.286  0.301  0.788  1.0
  Zn  Zn2  1  0.713  0.669  0.203  1.0
  Fe  Fe3  1  0.499  0.486  0.996  1.0
  Fe  Fe4  1  0.500  0.986  0.996  1.0
  Si  Si5  1  0.526  0.238  0.341  1.0
  Si  Si6  1  0.472  0.734  0.652  1.0
  O  O7  1  0.470  0.065  0.251  1.0
  O  O8  1  0.687  0.376  0.140  1.0
  O  O9  1  0.528  0.907  0.742  1.0
  O  O10  1  0.312  0.595  0.852  1.0
  O  O11  1  0.898  0.586  0.344  1.0
  O  O12  1  0.167  0.837  0.646  1.0
  O  O13  1  0.100  0.386  0.648  1.0
  O  O14  1  0.831  0.135  0.347  1.0
  O  O15  1  0.444  0.755  0.123  1.0
  O  O16  1  0.555  0.217  0.869  1.0
[/CIF]
.