The crystal structure described by Sr2Fe3Sb(PO4)6 crystallizes in the trigonal R3 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted hexagonal planar geometry to three equivalent O(5) and three equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a distorted hexagonal planar geometry to three equivalent O(6) and three equivalent O(8) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to three equivalent O(3) and three equivalent O(7) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to three equivalent O(4) and three equivalent O(8) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. Sb(1) is bonded to three equivalent O(1) and three equivalent O(5) atoms to form SbO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and  a cornercorner with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-37°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and  a cornercorner with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-35°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Sb(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(3) and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sr(1), one Sb(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Fe(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Sr(1), one Fe(2), and one P(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(2), one Fe(3), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2Fe3Sb(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.130
_cell_length_b   9.130
_cell_length_c   9.130
_cell_angle_alpha   56.243
_cell_angle_beta   56.243
_cell_angle_gamma   56.243
_symmetry_Int_Tables_number   1
_cell_volume   491.349
_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
  Sr  Sr0  1  0.504  0.504  0.504  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Fe  Fe2  1  0.850  0.850  0.850  1.0
  Fe  Fe3  1  0.650  0.650  0.650  1.0
  Fe  Fe4  1  0.149  0.149  0.149  1.0
  Sb  Sb5  1  0.350  0.350  0.350  1.0
  P  P6  1  0.958  0.538  0.249  1.0
  P  P7  1  0.249  0.958  0.538  1.0
  P  P8  1  0.538  0.249  0.958  1.0
  P  P9  1  0.753  0.034  0.462  1.0
  P  P10  1  0.462  0.753  0.034  1.0
  P  P11  1  0.034  0.462  0.753  1.0
  O  O12  1  0.135  0.521  0.263  1.0
  O  O13  1  0.263  0.135  0.521  1.0
  O  O14  1  0.521  0.263  0.135  1.0
  O  O15  1  0.762  0.019  0.633  1.0
  O  O16  1  0.633  0.762  0.019  1.0
  O  O17  1  0.019  0.633  0.762  1.0
  O  O18  1  0.869  0.484  0.730  1.0
  O  O19  1  0.730  0.869  0.484  1.0
  O  O20  1  0.484  0.730  0.869  1.0
  O  O21  1  0.234  0.987  0.365  1.0
  O  O22  1  0.365  0.234  0.987  1.0
  O  O23  1  0.987  0.365  0.234  1.0
  O  O24  1  0.221  0.435  0.569  1.0
  O  O25  1  0.569  0.221  0.435  1.0
  O  O26  1  0.435  0.569  0.221  1.0
  O  O27  1  0.074  0.937  0.718  1.0
  O  O28  1  0.718  0.074  0.937  1.0
  O  O29  1  0.937  0.718  0.074  1.0
  O  O30  1  0.784  0.565  0.426  1.0
  O  O31  1  0.426  0.784  0.565  1.0
  O  O32  1  0.565  0.426  0.784  1.0
  O  O33  1  0.922  0.070  0.280  1.0
  O  O34  1  0.280  0.922  0.070  1.0
  O  O35  1  0.070  0.280  0.922  1.0
[/CIF]
.
The crystal structure described by Sr2Fe3Sb(PO4)6 crystallizes in the trigonal R3 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted hexagonal planar geometry to three equivalent O(5) and three equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a distorted hexagonal planar geometry to three equivalent O(6) and three equivalent O(8) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to three equivalent O(3) and three equivalent O(7) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to three equivalent O(4) and three equivalent O(8) atoms to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. Sb(1) is bonded to three equivalent O(1) and three equivalent O(5) atoms to form SbO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and  a cornercorner with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-37°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and  a cornercorner with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-35°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Sb(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(3) and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sr(1), one Sb(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Fe(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Sr(1), one Fe(2), and one P(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(2), one Fe(3), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2Fe3Sb(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.130
_cell_length_b   9.130
_cell_length_c   9.130
_cell_angle_alpha   56.243
_cell_angle_beta   56.243
_cell_angle_gamma   56.243
_symmetry_Int_Tables_number   1
_cell_volume   491.349
_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
  Sr  Sr0  1  0.504  0.504  0.504  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Fe  Fe2  1  0.850  0.850  0.850  1.0
  Fe  Fe3  1  0.650  0.650  0.650  1.0
  Fe  Fe4  1  0.149  0.149  0.149  1.0
  Sb  Sb5  1  0.350  0.350  0.350  1.0
  P  P6  1  0.958  0.538  0.249  1.0
  P  P7  1  0.249  0.958  0.538  1.0
  P  P8  1  0.538  0.249  0.958  1.0
  P  P9  1  0.753  0.034  0.462  1.0
  P  P10  1  0.462  0.753  0.034  1.0
  P  P11  1  0.034  0.462  0.753  1.0
  O  O12  1  0.135  0.521  0.263  1.0
  O  O13  1  0.263  0.135  0.521  1.0
  O  O14  1  0.521  0.263  0.135  1.0
  O  O15  1  0.762  0.019  0.633  1.0
  O  O16  1  0.633  0.762  0.019  1.0
  O  O17  1  0.019  0.633  0.762  1.0
  O  O18  1  0.869  0.484  0.730  1.0
  O  O19  1  0.730  0.869  0.484  1.0
  O  O20  1  0.484  0.730  0.869  1.0
  O  O21  1  0.234  0.987  0.365  1.0
  O  O22  1  0.365  0.234  0.987  1.0
  O  O23  1  0.987  0.365  0.234  1.0
  O  O24  1  0.221  0.435  0.569  1.0
  O  O25  1  0.569  0.221  0.435  1.0
  O  O26  1  0.435  0.569  0.221  1.0
  O  O27  1  0.074  0.937  0.718  1.0
  O  O28  1  0.718  0.074  0.937  1.0
  O  O29  1  0.937  0.718  0.074  1.0
  O  O30  1  0.784  0.565  0.426  1.0
  O  O31  1  0.426  0.784  0.565  1.0
  O  O32  1  0.565  0.426  0.784  1.0
  O  O33  1  0.922  0.070  0.280  1.0
  O  O34  1  0.280  0.922  0.070  1.0
  O  O35  1  0.070  0.280  0.922  1.0
[/CIF]
.