The compound described by MgFe3(PO4)3 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(11), one O(12), one O(2), and one O(8) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(3), one O(4), and one O(9) atom to form distorted FeO4 tetrahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with two equivalent P(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(11), one O(6), and one O(8) atom to form distorted FeO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(3)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to one O(12), one O(2), one O(5), and one O(7) atom to form FeO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(12), one O(2), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Fe(2)O4 trigonal pyramids and corners with two equivalent Fe(3)O4 trigonal pyramids. In the second P site, P(2) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra and corners with two equivalent Fe(3)O4 trigonal pyramids. In the third P site, P(3) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra and corners with two equivalent Fe(2)O4 trigonal pyramids. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one P(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(3), and one P(1) atom. In the third O site, O(3) is bonded in a linear geometry to one Fe(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Fe(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(3) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(3) and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Fe(1) and one P(3) atom. In the tenth O site, O(10) is bonded in a linear geometry to one Fe(1) and one P(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one P(1) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(3), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe3(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.438
_cell_length_b   5.547
_cell_length_c   11.698
_cell_angle_alpha   89.984
_cell_angle_beta   90.021
_cell_angle_gamma   120.794
_symmetry_Int_Tables_number   1
_cell_volume   303.113
_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  1.000  0.340  1.0
  Fe  Fe1  1  0.000  0.500  0.832  1.0
  Fe  Fe2  1  0.500  0.500  0.142  1.0
  Fe  Fe3  1  0.500  1.000  0.529  1.0
  P  P4  1  1.000  0.500  0.335  1.0
  P  P5  1  0.500  0.500  0.655  1.0
  P  P6  1  0.501  0.001  0.008  1.0
  O  O7  1  0.629  0.867  0.084  1.0
  O  O8  1  0.182  0.775  0.406  1.0
  O  O9  1  0.260  0.486  0.731  1.0
  O  O10  1  0.739  0.514  0.732  1.0
  O  O11  1  0.361  0.236  0.579  1.0
  O  O12  1  0.371  0.133  0.084  1.0
  O  O13  1  0.639  0.763  0.579  1.0
  O  O14  1  0.819  0.596  0.266  1.0
  O  O15  1  0.747  0.219  0.932  1.0
  O  O16  1  0.256  0.783  0.931  1.0
  O  O17  1  0.180  0.404  0.266  1.0
  O  O18  1  0.818  0.224  0.406  1.0
[/CIF]
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The compound described by MgFe3(PO4)3 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(11), one O(12), one O(2), and one O(8) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(3), one O(4), and one O(9) atom to form distorted FeO4 tetrahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with two equivalent P(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(11), one O(6), and one O(8) atom to form distorted FeO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(3)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to one O(12), one O(2), one O(5), and one O(7) atom to form FeO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(12), one O(2), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Fe(2)O4 trigonal pyramids and corners with two equivalent Fe(3)O4 trigonal pyramids. In the second P site, P(2) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra and corners with two equivalent Fe(3)O4 trigonal pyramids. In the third P site, P(3) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra and corners with two equivalent Fe(2)O4 trigonal pyramids. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one P(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(3), and one P(1) atom. In the third O site, O(3) is bonded in a linear geometry to one Fe(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Fe(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(3) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(3) and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Fe(1) and one P(3) atom. In the tenth O site, O(10) is bonded in a linear geometry to one Fe(1) and one P(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one P(1) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(3), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe3(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.438
_cell_length_b   5.547
_cell_length_c   11.698
_cell_angle_alpha   89.984
_cell_angle_beta   90.021
_cell_angle_gamma   120.794
_symmetry_Int_Tables_number   1
_cell_volume   303.113
_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  1.000  0.340  1.0
  Fe  Fe1  1  0.000  0.500  0.832  1.0
  Fe  Fe2  1  0.500  0.500  0.142  1.0
  Fe  Fe3  1  0.500  1.000  0.529  1.0
  P  P4  1  1.000  0.500  0.335  1.0
  P  P5  1  0.500  0.500  0.655  1.0
  P  P6  1  0.501  0.001  0.008  1.0
  O  O7  1  0.629  0.867  0.084  1.0
  O  O8  1  0.182  0.775  0.406  1.0
  O  O9  1  0.260  0.486  0.731  1.0
  O  O10  1  0.739  0.514  0.732  1.0
  O  O11  1  0.361  0.236  0.579  1.0
  O  O12  1  0.371  0.133  0.084  1.0
  O  O13  1  0.639  0.763  0.579  1.0
  O  O14  1  0.819  0.596  0.266  1.0
  O  O15  1  0.747  0.219  0.932  1.0
  O  O16  1  0.256  0.783  0.931  1.0
  O  O17  1  0.180  0.404  0.266  1.0
  O  O18  1  0.818  0.224  0.406  1.0
[/CIF]
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