The structure described by Sr4FeTaO8 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to two equivalent O(3), three equivalent O(2), and four equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(3), and four equivalent O(1) atoms. Ta(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedra are not tilted. Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedra are not tilted. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Fe(1) atom to form distorted OSr4TaFe octahedra that share corners with two equivalent O(1)Sr4TaFe octahedra, corners with six equivalent O(2)Sr5Fe octahedra, corners with six equivalent O(3)Sr5Ta octahedra, edges with two equivalent O(1)Sr4TaFe octahedra, faces with two equivalent O(2)Sr5Fe octahedra, faces with two equivalent O(3)Sr5Ta octahedra, and faces with four equivalent O(1)Sr4TaFe octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the second O site, O(2) is bonded to two equivalent Sr(2), three equivalent Sr(1), and one Fe(1) atom to form distorted OSr5Fe octahedra that share corners with five equivalent O(2)Sr5Fe octahedra, corners with twelve equivalent O(1)Sr4TaFe octahedra, edges with two equivalent O(2)Sr5Fe octahedra, edges with six equivalent O(3)Sr5Ta octahedra, and faces with four equivalent O(1)Sr4TaFe octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the third O site, O(3) is bonded to two equivalent Sr(1), three equivalent Sr(2), and one Ta(1) atom to form distorted OSr5Ta octahedra that share corners with five equivalent O(3)Sr5Ta octahedra, corners with twelve equivalent O(1)Sr4TaFe octahedra, edges with two equivalent O(3)Sr5Ta octahedra, edges with six equivalent O(2)Sr5Fe octahedra, and faces with four equivalent O(1)Sr4TaFe octahedra. The corner-sharing octahedral tilt angles range from 0-56°. is represented by the CIF file [CIF]
data_Sr4TaFeO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.982
_cell_length_b   6.982
_cell_length_c   5.641
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   132.319
_symmetry_Int_Tables_number   1
_cell_volume   203.313
_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  0.648  0.352  0.000  1.0
  Sr  Sr1  1  0.146  0.854  0.500  1.0
  Sr  Sr2  1  0.854  0.146  0.500  1.0
  Sr  Sr3  1  0.352  0.648  0.000  1.0
  Ta  Ta4  1  0.500  0.500  0.500  1.0
  Fe  Fe5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.748  0.748  0.747  1.0
  O  O7  1  0.252  0.252  0.253  1.0
  O  O8  1  0.252  0.252  0.747  1.0
  O  O9  1  0.748  0.748  0.253  1.0
  O  O10  1  0.838  0.162  0.000  1.0
  O  O11  1  0.340  0.660  0.500  1.0
  O  O12  1  0.660  0.340  0.500  1.0
  O  O13  1  0.162  0.838  0.000  1.0
[/CIF]
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The structure described by Sr4FeTaO8 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to two equivalent O(3), three equivalent O(2), and four equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(3), and four equivalent O(1) atoms. Ta(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedra are not tilted. Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedra are not tilted. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Fe(1) atom to form distorted OSr4TaFe octahedra that share corners with two equivalent O(1)Sr4TaFe octahedra, corners with six equivalent O(2)Sr5Fe octahedra, corners with six equivalent O(3)Sr5Ta octahedra, edges with two equivalent O(1)Sr4TaFe octahedra, faces with two equivalent O(2)Sr5Fe octahedra, faces with two equivalent O(3)Sr5Ta octahedra, and faces with four equivalent O(1)Sr4TaFe octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the second O site, O(2) is bonded to two equivalent Sr(2), three equivalent Sr(1), and one Fe(1) atom to form distorted OSr5Fe octahedra that share corners with five equivalent O(2)Sr5Fe octahedra, corners with twelve equivalent O(1)Sr4TaFe octahedra, edges with two equivalent O(2)Sr5Fe octahedra, edges with six equivalent O(3)Sr5Ta octahedra, and faces with four equivalent O(1)Sr4TaFe octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the third O site, O(3) is bonded to two equivalent Sr(1), three equivalent Sr(2), and one Ta(1) atom to form distorted OSr5Ta octahedra that share corners with five equivalent O(3)Sr5Ta octahedra, corners with twelve equivalent O(1)Sr4TaFe octahedra, edges with two equivalent O(3)Sr5Ta octahedra, edges with six equivalent O(2)Sr5Fe octahedra, and faces with four equivalent O(1)Sr4TaFe octahedra. The corner-sharing octahedral tilt angles range from 0-56°. is represented by the CIF file [CIF]
data_Sr4TaFeO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.982
_cell_length_b   6.982
_cell_length_c   5.641
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   132.319
_symmetry_Int_Tables_number   1
_cell_volume   203.313
_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  0.648  0.352  0.000  1.0
  Sr  Sr1  1  0.146  0.854  0.500  1.0
  Sr  Sr2  1  0.854  0.146  0.500  1.0
  Sr  Sr3  1  0.352  0.648  0.000  1.0
  Ta  Ta4  1  0.500  0.500  0.500  1.0
  Fe  Fe5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.748  0.748  0.747  1.0
  O  O7  1  0.252  0.252  0.253  1.0
  O  O8  1  0.252  0.252  0.747  1.0
  O  O9  1  0.748  0.748  0.253  1.0
  O  O10  1  0.838  0.162  0.000  1.0
  O  O11  1  0.340  0.660  0.500  1.0
  O  O12  1  0.660  0.340  0.500  1.0
  O  O13  1  0.162  0.838  0.000  1.0
[/CIF]
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