The structure described by MgFe2Zn2(SiO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(5), and one O(8) 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(7), and one O(9) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids, and  an edgeedge with one Zn(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(10), one O(3), one O(6), and one O(9) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Zn(2)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 4-coordinate geometry to one O(10), one O(3), one O(7), and one O(8) atom. In the second Zn site, Zn(2) is bonded to one O(2), one O(5), one O(6), and one O(9) atom to form distorted ZnO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Si(2)O4 tetrahedra. 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)O5 square pyramids,  a cornercorner with one Zn(2)O4 tetrahedra, and  a cornercorner with one Fe(2)O5 trigonal bipyramid. 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  a cornercorner with one Fe(1)O5 square pyramid, corners with two equivalent Fe(2)O5 trigonal bipyramids, and  an edgeedge with one Zn(2)O4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), 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 Fe(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(2), one Zn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Zn(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Fe(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted 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 distorted T-shaped geometry to one Mg(1), one Zn(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Zn(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal pyramidal geometry to one Mg(1), one Fe(1), one Fe(2), and one Zn(1) atom. is represented by the CIF file [CIF]
data_MgZn2Fe2(SiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.754
_cell_length_b   7.344
_cell_length_c   7.957
_cell_angle_alpha   90.957
_cell_angle_beta   45.623
_cell_angle_gamma   72.372
_symmetry_Int_Tables_number   1
_cell_volume   215.784
_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  0.022  0.345  0.317  1.0
  Zn  Zn1  1  0.460  0.191  0.710  1.0
  Zn  Zn2  1  0.459  0.713  0.330  1.0
  Fe  Fe3  1  0.582  0.474  0.947  1.0
  Fe  Fe4  1  0.635  0.951  0.944  1.0
  Si  Si5  1  0.444  0.260  0.390  1.0
  Si  Si6  1  0.533  0.736  0.626  1.0
  O  O7  1  0.398  0.099  0.279  1.0
  O  O8  1  0.409  0.448  0.286  1.0
  O  O9  1  0.582  0.905  0.721  1.0
  O  O10  1  0.589  0.532  0.703  1.0
  O  O11  1  0.840  0.633  0.318  1.0
  O  O12  1  0.158  0.838  0.701  1.0
  O  O13  1  0.109  0.326  0.702  1.0
  O  O14  1  0.789  0.180  0.342  1.0
  O  O15  1  0.518  0.736  0.066  1.0
  O  O16  1  0.471  0.242  0.943  1.0
[/CIF]
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The structure described by MgFe2Zn2(SiO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(5), and one O(8) 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(7), and one O(9) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids, and  an edgeedge with one Zn(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(10), one O(3), one O(6), and one O(9) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Zn(2)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 4-coordinate geometry to one O(10), one O(3), one O(7), and one O(8) atom. In the second Zn site, Zn(2) is bonded to one O(2), one O(5), one O(6), and one O(9) atom to form distorted ZnO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Si(2)O4 tetrahedra. 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)O5 square pyramids,  a cornercorner with one Zn(2)O4 tetrahedra, and  a cornercorner with one Fe(2)O5 trigonal bipyramid. 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  a cornercorner with one Fe(1)O5 square pyramid, corners with two equivalent Fe(2)O5 trigonal bipyramids, and  an edgeedge with one Zn(2)O4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), 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 Fe(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(2), one Zn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Zn(2), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Fe(2), one Zn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted 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 distorted T-shaped geometry to one Mg(1), one Zn(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Zn(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal pyramidal geometry to one Mg(1), one Fe(1), one Fe(2), and one Zn(1) atom. is represented by the CIF file [CIF]
data_MgZn2Fe2(SiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.754
_cell_length_b   7.344
_cell_length_c   7.957
_cell_angle_alpha   90.957
_cell_angle_beta   45.623
_cell_angle_gamma   72.372
_symmetry_Int_Tables_number   1
_cell_volume   215.784
_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  0.022  0.345  0.317  1.0
  Zn  Zn1  1  0.460  0.191  0.710  1.0
  Zn  Zn2  1  0.459  0.713  0.330  1.0
  Fe  Fe3  1  0.582  0.474  0.947  1.0
  Fe  Fe4  1  0.635  0.951  0.944  1.0
  Si  Si5  1  0.444  0.260  0.390  1.0
  Si  Si6  1  0.533  0.736  0.626  1.0
  O  O7  1  0.398  0.099  0.279  1.0
  O  O8  1  0.409  0.448  0.286  1.0
  O  O9  1  0.582  0.905  0.721  1.0
  O  O10  1  0.589  0.532  0.703  1.0
  O  O11  1  0.840  0.633  0.318  1.0
  O  O12  1  0.158  0.838  0.701  1.0
  O  O13  1  0.109  0.326  0.702  1.0
  O  O14  1  0.789  0.180  0.342  1.0
  O  O15  1  0.518  0.736  0.066  1.0
  O  O16  1  0.471  0.242  0.943  1.0
[/CIF]
.