The material described by Co3(AsO4)2 crystallizes in the tetragonal I-4 space group. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CoO6 octahedra that share  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one Co(4)O6 octahedra,  a cornercorner with one As(1)O4 tetrahedra,  a cornercorner with one As(3)O4 tetrahedra, corners with two equivalent As(2)O4 tetrahedra,  an edgeedge with one Co(2)O6 octahedra,  an edgeedge with one Co(4)O6 octahedra, and  an edgeedge with one As(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-61°. In the second Co site, Co(2) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent As(3)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra, and edges with two equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. In the third Co site, Co(3) is bonded in a 4-coordinate geometry to four equivalent O(5) atoms. In the fourth Co site, Co(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent As(1)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra, and edges with two equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are three inequivalent As sites. In the first As site, As(1) is bonded to four equivalent O(1) atoms to form AsO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra and corners with four equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the second As site, As(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form AsO4 tetrahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, and  an edgeedge with one Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-54°. In the third As site, As(3) is bonded to four equivalent O(6) atoms to form AsO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra and corners with four equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-52°. There are six inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to one Co(1), one Co(2), and one As(2) atom. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one As(2) atom. In the third O site, O(5) is bonded to one Co(1), one Co(2), one Co(3), and one As(2) atom to form corner-sharing OCo3As tetrahedra. In the fourth O site, O(6) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one As(3) atom. In the fifth O site, O(1) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one As(1) atom. In the sixth O site, O(2) is bonded in a 3-coordinate geometry to one Co(1), one Co(4), and one As(2) atom. is represented by the CIF card [CIF]
data_Co3(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.657
_cell_length_b   10.657
_cell_length_c   10.657
_cell_angle_alpha   141.870
_cell_angle_beta   141.870
_cell_angle_gamma   55.025
_symmetry_Int_Tables_number   1
_cell_volume   458.115
_cell_formula_units_Z   3
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  0.130  0.630  0.008  1.0
  Co  Co1  1  0.226  0.226  0.000  1.0
  Co  Co2  1  0.750  0.250  0.500  1.0
  Co  Co3  1  0.878  0.870  0.500  1.0
  Co  Co4  1  0.622  0.122  0.992  1.0
  Co  Co5  1  0.479  0.979  0.500  1.0
  Co  Co6  1  0.021  0.521  0.500  1.0
  Co  Co7  1  0.774  0.774  0.000  1.0
  Co  Co8  1  0.370  0.378  0.500  1.0
  As  As9  1  0.000  0.000  0.000  1.0
  As  As10  1  0.628  0.532  0.407  1.0
  As  As11  1  0.125  0.221  0.593  1.0
  As  As12  1  0.468  0.875  0.096  1.0
  As  As13  1  0.250  0.750  0.500  1.0
  As  As14  1  0.779  0.372  0.904  1.0
  O  O15  1  0.166  0.902  0.157  1.0
  O  O16  1  0.442  0.676  0.329  1.0
  O  O17  1  0.807  0.624  0.732  1.0
  O  O18  1  0.925  0.193  0.817  1.0
  O  O19  1  0.146  0.456  0.718  1.0
  O  O20  1  0.077  0.308  0.779  1.0
  O  O21  1  0.529  0.299  0.221  1.0
  O  O22  1  0.737  0.427  0.282  1.0
  O  O23  1  0.376  0.108  0.183  1.0
  O  O24  1  0.991  0.834  0.736  1.0
  O  O25  1  0.573  0.854  0.310  1.0
  O  O26  1  0.347  0.113  0.671  1.0
  O  O27  1  0.892  0.075  0.268  1.0
  O  O28  1  0.701  0.923  0.231  1.0
  O  O29  1  0.147  0.918  0.651  1.0
  O  O30  1  0.745  0.009  0.843  1.0
  O  O31  1  0.504  0.853  0.771  1.0
  O  O32  1  0.324  0.653  0.765  1.0
  O  O33  1  0.887  0.558  0.235  1.0
  O  O34  1  0.082  0.733  0.229  1.0
  O  O35  1  0.267  0.496  0.349  1.0
  O  O36  1  0.692  0.471  0.769  1.0
  O  O37  1  0.544  0.263  0.690  1.0
  O  O38  1  0.098  0.255  0.264  1.0
[/CIF]
.
The material described by Co3(AsO4)2 crystallizes in the tetragonal I-4 space group. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CoO6 octahedra that share  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one Co(4)O6 octahedra,  a cornercorner with one As(1)O4 tetrahedra,  a cornercorner with one As(3)O4 tetrahedra, corners with two equivalent As(2)O4 tetrahedra,  an edgeedge with one Co(2)O6 octahedra,  an edgeedge with one Co(4)O6 octahedra, and  an edgeedge with one As(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-61°. In the second Co site, Co(2) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent As(3)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra, and edges with two equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 61°. In the third Co site, Co(3) is bonded in a 4-coordinate geometry to four equivalent O(5) atoms. In the fourth Co site, Co(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent As(1)O4 tetrahedra, corners with four equivalent As(2)O4 tetrahedra, and edges with two equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are three inequivalent As sites. In the first As site, As(1) is bonded to four equivalent O(1) atoms to form AsO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra and corners with four equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the second As site, As(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form AsO4 tetrahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, and  an edgeedge with one Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-54°. In the third As site, As(3) is bonded to four equivalent O(6) atoms to form AsO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra and corners with four equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-52°. There are six inequivalent O sites. In the first O site, O(3) is bonded in a 3-coordinate geometry to one Co(1), one Co(2), and one As(2) atom. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one As(2) atom. In the third O site, O(5) is bonded to one Co(1), one Co(2), one Co(3), and one As(2) atom to form corner-sharing OCo3As tetrahedra. In the fourth O site, O(6) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one As(3) atom. In the fifth O site, O(1) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one As(1) atom. In the sixth O site, O(2) is bonded in a 3-coordinate geometry to one Co(1), one Co(4), and one As(2) atom. is represented by the CIF card [CIF]
data_Co3(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.657
_cell_length_b   10.657
_cell_length_c   10.657
_cell_angle_alpha   141.870
_cell_angle_beta   141.870
_cell_angle_gamma   55.025
_symmetry_Int_Tables_number   1
_cell_volume   458.115
_cell_formula_units_Z   3
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  0.130  0.630  0.008  1.0
  Co  Co1  1  0.226  0.226  0.000  1.0
  Co  Co2  1  0.750  0.250  0.500  1.0
  Co  Co3  1  0.878  0.870  0.500  1.0
  Co  Co4  1  0.622  0.122  0.992  1.0
  Co  Co5  1  0.479  0.979  0.500  1.0
  Co  Co6  1  0.021  0.521  0.500  1.0
  Co  Co7  1  0.774  0.774  0.000  1.0
  Co  Co8  1  0.370  0.378  0.500  1.0
  As  As9  1  0.000  0.000  0.000  1.0
  As  As10  1  0.628  0.532  0.407  1.0
  As  As11  1  0.125  0.221  0.593  1.0
  As  As12  1  0.468  0.875  0.096  1.0
  As  As13  1  0.250  0.750  0.500  1.0
  As  As14  1  0.779  0.372  0.904  1.0
  O  O15  1  0.166  0.902  0.157  1.0
  O  O16  1  0.442  0.676  0.329  1.0
  O  O17  1  0.807  0.624  0.732  1.0
  O  O18  1  0.925  0.193  0.817  1.0
  O  O19  1  0.146  0.456  0.718  1.0
  O  O20  1  0.077  0.308  0.779  1.0
  O  O21  1  0.529  0.299  0.221  1.0
  O  O22  1  0.737  0.427  0.282  1.0
  O  O23  1  0.376  0.108  0.183  1.0
  O  O24  1  0.991  0.834  0.736  1.0
  O  O25  1  0.573  0.854  0.310  1.0
  O  O26  1  0.347  0.113  0.671  1.0
  O  O27  1  0.892  0.075  0.268  1.0
  O  O28  1  0.701  0.923  0.231  1.0
  O  O29  1  0.147  0.918  0.651  1.0
  O  O30  1  0.745  0.009  0.843  1.0
  O  O31  1  0.504  0.853  0.771  1.0
  O  O32  1  0.324  0.653  0.765  1.0
  O  O33  1  0.887  0.558  0.235  1.0
  O  O34  1  0.082  0.733  0.229  1.0
  O  O35  1  0.267  0.496  0.349  1.0
  O  O36  1  0.692  0.471  0.769  1.0
  O  O37  1  0.544  0.263  0.690  1.0
  O  O38  1  0.098  0.255  0.264  1.0
[/CIF]
.