The compound described by Sr3(Co0.5Nb0.5)2O7 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Aea2 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(3), and four equivalent O(5) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(2), and four equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(4) atoms. Nb(1) is bonded to one O(1), one O(3), and four equivalent O(5) atoms to form NbO6 octahedra that share  a cornercorner with one Co(1)O6 octahedra and corners with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. Co(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form distorted CoO6 octahedra that share  a cornercorner with one Nb(1)O6 octahedra and corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-12°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to four equivalent Sr(3), one Nb(1), and one Co(1) atom. In the second O site, O(2) is bonded to one Sr(1), four equivalent Sr(2), and one Co(1) atom to form distorted OSr5Co octahedra that share corners with four equivalent O(2)Sr5Co octahedra, corners with eight equivalent O(4)Sr4Co2 octahedra, edges with four equivalent O(2)Sr5Co octahedra, edges with four equivalent O(3)Sr5Nb octahedra, and faces with four equivalent O(4)Sr4Co2 octahedra. The corner-sharing octahedral tilt angles range from 14-56°. In the third O site, O(3) is bonded to one Sr(2), four equivalent Sr(1), and one Nb(1) atom to form OSr5Nb octahedra that share corners with four equivalent O(4)Sr4Co2 octahedra, corners with four equivalent O(3)Sr5Nb octahedra, edges with four equivalent O(2)Sr5Co octahedra, and edges with four equivalent O(3)Sr5Nb octahedra. The corner-sharing octahedral tilt angles range from 3-47°. In the fourth O site, O(4) is bonded to two equivalent Sr(2), two equivalent Sr(3), and two equivalent Co(1) atoms to form distorted OSr4Co2 octahedra that share corners with two equivalent O(4)Sr4Co2 octahedra, corners with two equivalent O(3)Sr5Nb octahedra, corners with four equivalent O(2)Sr5Co octahedra, edges with two equivalent O(4)Sr4Co2 octahedra, faces with two equivalent O(2)Sr5Co octahedra, and faces with four equivalent O(4)Sr4Co2 octahedra. The corner-sharing octahedral tilt angles range from 11-56°. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. is represented by the CIF file [CIF]
data_Sr3NbCoO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.619
_cell_length_b   11.082
_cell_length_c   5.618
_cell_angle_alpha   75.312
_cell_angle_beta   89.998
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   338.383
_cell_formula_units_Z   2
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  1.000  0.384  0.308  1.0
  Sr  Sr1  1  0.500  0.384  0.808  1.0
  Sr  Sr2  1  0.500  0.635  0.183  1.0
  Sr  Sr3  1  1.000  0.634  0.683  1.0
  Sr  Sr4  1  0.500  0.962  0.019  1.0
  Sr  Sr5  1  1.000  0.962  0.519  1.0
  Nb  Nb6  1  0.500  0.195  0.403  1.0
  Nb  Nb7  1  1.000  0.195  0.903  1.0
  Co  Co8  1  0.000  0.789  0.106  1.0
  Co  Co9  1  0.500  0.789  0.606  1.0
  O  O10  1  0.500  0.016  0.492  1.0
  O  O11  1  1.000  0.016  0.992  1.0
  O  O12  1  0.000  0.603  0.199  1.0
  O  O13  1  0.500  0.603  0.699  1.0
  O  O14  1  0.500  0.391  0.304  1.0
  O  O15  1  0.000  0.391  0.804  1.0
  O  O16  1  0.763  0.808  0.860  1.0
  O  O17  1  0.237  0.808  0.332  1.0
  O  O18  1  0.737  0.808  0.360  1.0
  O  O19  1  0.264  0.808  0.833  1.0
  O  O20  1  0.750  0.205  0.647  1.0
  O  O21  1  0.250  0.205  0.147  1.0
  O  O22  1  0.750  0.205  0.148  1.0
  O  O23  1  0.250  0.205  0.647  1.0
[/CIF]
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The compound described by Sr3(Co0.5Nb0.5)2O7 is (La,Ba)CuO4-derived structured and crystallizes in the orthorhombic Aea2 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(3), and four equivalent O(5) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(2), and four equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(4) atoms. Nb(1) is bonded to one O(1), one O(3), and four equivalent O(5) atoms to form NbO6 octahedra that share  a cornercorner with one Co(1)O6 octahedra and corners with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-6°. Co(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form distorted CoO6 octahedra that share  a cornercorner with one Nb(1)O6 octahedra and corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-12°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to four equivalent Sr(3), one Nb(1), and one Co(1) atom. In the second O site, O(2) is bonded to one Sr(1), four equivalent Sr(2), and one Co(1) atom to form distorted OSr5Co octahedra that share corners with four equivalent O(2)Sr5Co octahedra, corners with eight equivalent O(4)Sr4Co2 octahedra, edges with four equivalent O(2)Sr5Co octahedra, edges with four equivalent O(3)Sr5Nb octahedra, and faces with four equivalent O(4)Sr4Co2 octahedra. The corner-sharing octahedral tilt angles range from 14-56°. In the third O site, O(3) is bonded to one Sr(2), four equivalent Sr(1), and one Nb(1) atom to form OSr5Nb octahedra that share corners with four equivalent O(4)Sr4Co2 octahedra, corners with four equivalent O(3)Sr5Nb octahedra, edges with four equivalent O(2)Sr5Co octahedra, and edges with four equivalent O(3)Sr5Nb octahedra. The corner-sharing octahedral tilt angles range from 3-47°. In the fourth O site, O(4) is bonded to two equivalent Sr(2), two equivalent Sr(3), and two equivalent Co(1) atoms to form distorted OSr4Co2 octahedra that share corners with two equivalent O(4)Sr4Co2 octahedra, corners with two equivalent O(3)Sr5Nb octahedra, corners with four equivalent O(2)Sr5Co octahedra, edges with two equivalent O(4)Sr4Co2 octahedra, faces with two equivalent O(2)Sr5Co octahedra, and faces with four equivalent O(4)Sr4Co2 octahedra. The corner-sharing octahedral tilt angles range from 11-56°. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. is represented by the CIF file [CIF]
data_Sr3NbCoO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.619
_cell_length_b   11.082
_cell_length_c   5.618
_cell_angle_alpha   75.312
_cell_angle_beta   89.998
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   338.383
_cell_formula_units_Z   2
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  1.000  0.384  0.308  1.0
  Sr  Sr1  1  0.500  0.384  0.808  1.0
  Sr  Sr2  1  0.500  0.635  0.183  1.0
  Sr  Sr3  1  1.000  0.634  0.683  1.0
  Sr  Sr4  1  0.500  0.962  0.019  1.0
  Sr  Sr5  1  1.000  0.962  0.519  1.0
  Nb  Nb6  1  0.500  0.195  0.403  1.0
  Nb  Nb7  1  1.000  0.195  0.903  1.0
  Co  Co8  1  0.000  0.789  0.106  1.0
  Co  Co9  1  0.500  0.789  0.606  1.0
  O  O10  1  0.500  0.016  0.492  1.0
  O  O11  1  1.000  0.016  0.992  1.0
  O  O12  1  0.000  0.603  0.199  1.0
  O  O13  1  0.500  0.603  0.699  1.0
  O  O14  1  0.500  0.391  0.304  1.0
  O  O15  1  0.000  0.391  0.804  1.0
  O  O16  1  0.763  0.808  0.860  1.0
  O  O17  1  0.237  0.808  0.332  1.0
  O  O18  1  0.737  0.808  0.360  1.0
  O  O19  1  0.264  0.808  0.833  1.0
  O  O20  1  0.750  0.205  0.647  1.0
  O  O21  1  0.250  0.205  0.147  1.0
  O  O22  1  0.750  0.205  0.148  1.0
  O  O23  1  0.250  0.205  0.647  1.0
[/CIF]
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