The crystal structure described by Co7(AsO6)2 crystallizes in the orthorhombic Imma space group. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(5), and two equivalent O(1) atoms to form CoO4 tetrahedra that share corners with three equivalent Co(3)O6 octahedra, corners with three equivalent As(2)O6 octahedra, corners with four equivalent Co(2)O6 octahedra, and  a cornercorner with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-67°. In the second Co site, Co(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with two equivalent Co(4)O6 octahedra, corners with four equivalent Co(1)O4 tetrahedra,  an edgeedge with one Co(4)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent As(2)O6 octahedra. The corner-sharing octahedral tilt angles are 13°. In the third Co site, Co(3) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form CoO6 octahedra that share corners with three equivalent Co(1)O4 tetrahedra, corners with three equivalent As(1)O4 tetrahedra,  an edgeedge with one Co(3)O6 octahedra,  an edgeedge with one As(2)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. In the fourth Co site, Co(4) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form CoO6 octahedra that share corners with four equivalent Co(2)O6 octahedra, corners with two equivalent As(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with four equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles are 13°. There are two inequivalent As sites. In the first As site, As(1) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form AsO4 tetrahedra that share corners with two equivalent Co(4)O6 octahedra, corners with six equivalent Co(3)O6 octahedra, and corners with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-57°. In the second As site, As(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form AsO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one As(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Co(4), two equivalent Co(3), and one As(1) atom. In the third O site, O(3) is bonded to one Co(1), two equivalent Co(2), and one As(2) atom to form distorted OCo3As tetrahedra that share corners with two equivalent O(4)Co5 square pyramids, corners with three equivalent O(3)Co3As tetrahedra, and  an edgeedge with one O(4)Co5 square pyramid. In the fourth O site, O(4) is bonded to one Co(3), two equivalent Co(2), and two equivalent Co(4) atoms to form OCo5 square pyramids that share corners with two equivalent O(4)Co5 square pyramids, corners with two equivalent O(3)Co3As tetrahedra, edges with three equivalent O(4)Co5 square pyramids, and  an edgeedge with one O(3)Co3As tetrahedra. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Co(1), one Co(3), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Co7(AsO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.530
_cell_length_b   10.530
_cell_length_c   10.530
_cell_angle_alpha   147.341
_cell_angle_beta   132.012
_cell_angle_gamma   59.257
_symmetry_Int_Tables_number   1
_cell_volume   464.126
_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
  Co  Co0  1  0.799  0.428  0.371  1.0
  Co  Co1  1  0.162  0.662  0.000  1.0
  Co  Co2  1  0.162  0.162  0.500  1.0
  Co  Co3  1  0.816  0.836  0.980  1.0
  Co  Co4  1  0.838  0.838  0.500  1.0
  Co  Co5  1  0.184  0.164  0.020  1.0
  Co  Co6  1  0.201  0.572  0.629  1.0
  Co  Co7  1  0.644  0.664  0.980  1.0
  Co  Co8  1  0.000  0.000  0.500  1.0
  Co  Co9  1  0.838  0.338  0.000  1.0
  Co  Co10  1  0.356  0.336  0.020  1.0
  Co  Co11  1  0.443  0.072  0.371  1.0
  Co  Co12  1  0.557  0.928  0.629  1.0
  Co  Co13  1  0.000  0.500  0.000  1.0
  As  As14  1  0.372  0.750  0.622  1.0
  As  As15  1  0.628  0.250  0.378  1.0
  As  As16  1  0.000  0.000  0.000  1.0
  As  As17  1  0.500  0.500  0.000  1.0
  O  O18  1  0.922  0.146  0.216  1.0
  O  O19  1  0.741  0.008  0.249  1.0
  O  O20  1  0.741  0.492  0.733  1.0
  O  O21  1  0.728  0.509  0.219  1.0
  O  O22  1  0.430  0.206  0.784  1.0
  O  O23  1  0.210  0.991  0.219  1.0
  O  O24  1  0.259  0.992  0.751  1.0
  O  O25  1  0.430  0.646  0.224  1.0
  O  O26  1  0.922  0.706  0.776  1.0
  O  O27  1  0.947  0.169  0.778  1.0
  O  O28  1  0.892  0.669  0.222  1.0
  O  O29  1  0.570  0.794  0.216  1.0
  O  O30  1  0.078  0.854  0.784  1.0
  O  O31  1  0.272  0.491  0.781  1.0
  O  O32  1  0.564  0.829  0.735  1.0
  O  O33  1  0.594  0.329  0.265  1.0
  O  O34  1  0.259  0.508  0.267  1.0
  O  O35  1  0.436  0.171  0.265  1.0
  O  O36  1  0.406  0.671  0.735  1.0
  O  O37  1  0.078  0.294  0.224  1.0
  O  O38  1  0.053  0.831  0.222  1.0
  O  O39  1  0.790  0.009  0.781  1.0
  O  O40  1  0.570  0.354  0.776  1.0
  O  O41  1  0.108  0.331  0.778  1.0
[/CIF]
.
The crystal structure described by Co7(AsO6)2 crystallizes in the orthorhombic Imma space group. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(5), and two equivalent O(1) atoms to form CoO4 tetrahedra that share corners with three equivalent Co(3)O6 octahedra, corners with three equivalent As(2)O6 octahedra, corners with four equivalent Co(2)O6 octahedra, and  a cornercorner with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-67°. In the second Co site, Co(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with two equivalent Co(4)O6 octahedra, corners with four equivalent Co(1)O4 tetrahedra,  an edgeedge with one Co(4)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent As(2)O6 octahedra. The corner-sharing octahedral tilt angles are 13°. In the third Co site, Co(3) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form CoO6 octahedra that share corners with three equivalent Co(1)O4 tetrahedra, corners with three equivalent As(1)O4 tetrahedra,  an edgeedge with one Co(3)O6 octahedra,  an edgeedge with one As(2)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. In the fourth Co site, Co(4) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form CoO6 octahedra that share corners with four equivalent Co(2)O6 octahedra, corners with two equivalent As(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with four equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles are 13°. There are two inequivalent As sites. In the first As site, As(1) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form AsO4 tetrahedra that share corners with two equivalent Co(4)O6 octahedra, corners with six equivalent Co(3)O6 octahedra, and corners with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-57°. In the second As site, As(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form AsO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one As(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Co(4), two equivalent Co(3), and one As(1) atom. In the third O site, O(3) is bonded to one Co(1), two equivalent Co(2), and one As(2) atom to form distorted OCo3As tetrahedra that share corners with two equivalent O(4)Co5 square pyramids, corners with three equivalent O(3)Co3As tetrahedra, and  an edgeedge with one O(4)Co5 square pyramid. In the fourth O site, O(4) is bonded to one Co(3), two equivalent Co(2), and two equivalent Co(4) atoms to form OCo5 square pyramids that share corners with two equivalent O(4)Co5 square pyramids, corners with two equivalent O(3)Co3As tetrahedra, edges with three equivalent O(4)Co5 square pyramids, and  an edgeedge with one O(3)Co3As tetrahedra. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Co(1), one Co(3), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Co7(AsO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.530
_cell_length_b   10.530
_cell_length_c   10.530
_cell_angle_alpha   147.341
_cell_angle_beta   132.012
_cell_angle_gamma   59.257
_symmetry_Int_Tables_number   1
_cell_volume   464.126
_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
  Co  Co0  1  0.799  0.428  0.371  1.0
  Co  Co1  1  0.162  0.662  0.000  1.0
  Co  Co2  1  0.162  0.162  0.500  1.0
  Co  Co3  1  0.816  0.836  0.980  1.0
  Co  Co4  1  0.838  0.838  0.500  1.0
  Co  Co5  1  0.184  0.164  0.020  1.0
  Co  Co6  1  0.201  0.572  0.629  1.0
  Co  Co7  1  0.644  0.664  0.980  1.0
  Co  Co8  1  0.000  0.000  0.500  1.0
  Co  Co9  1  0.838  0.338  0.000  1.0
  Co  Co10  1  0.356  0.336  0.020  1.0
  Co  Co11  1  0.443  0.072  0.371  1.0
  Co  Co12  1  0.557  0.928  0.629  1.0
  Co  Co13  1  0.000  0.500  0.000  1.0
  As  As14  1  0.372  0.750  0.622  1.0
  As  As15  1  0.628  0.250  0.378  1.0
  As  As16  1  0.000  0.000  0.000  1.0
  As  As17  1  0.500  0.500  0.000  1.0
  O  O18  1  0.922  0.146  0.216  1.0
  O  O19  1  0.741  0.008  0.249  1.0
  O  O20  1  0.741  0.492  0.733  1.0
  O  O21  1  0.728  0.509  0.219  1.0
  O  O22  1  0.430  0.206  0.784  1.0
  O  O23  1  0.210  0.991  0.219  1.0
  O  O24  1  0.259  0.992  0.751  1.0
  O  O25  1  0.430  0.646  0.224  1.0
  O  O26  1  0.922  0.706  0.776  1.0
  O  O27  1  0.947  0.169  0.778  1.0
  O  O28  1  0.892  0.669  0.222  1.0
  O  O29  1  0.570  0.794  0.216  1.0
  O  O30  1  0.078  0.854  0.784  1.0
  O  O31  1  0.272  0.491  0.781  1.0
  O  O32  1  0.564  0.829  0.735  1.0
  O  O33  1  0.594  0.329  0.265  1.0
  O  O34  1  0.259  0.508  0.267  1.0
  O  O35  1  0.436  0.171  0.265  1.0
  O  O36  1  0.406  0.671  0.735  1.0
  O  O37  1  0.078  0.294  0.224  1.0
  O  O38  1  0.053  0.831  0.222  1.0
  O  O39  1  0.790  0.009  0.781  1.0
  O  O40  1  0.570  0.354  0.776  1.0
  O  O41  1  0.108  0.331  0.778  1.0
[/CIF]
.