The crystal structure described by BaCo2(AsO4)2 crystallizes in the triclinic P1 space group. Ba(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), one O(8), three equivalent O(6), and three equivalent O(7) atoms to form distorted BaO12 cuboctahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, edges with six equivalent Ba(1)O12 cuboctahedra, edges with three equivalent As(1)O4 tetrahedra, edges with three equivalent As(2)O4 tetrahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-47°. There are two 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(8) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent As(1)O4 tetrahedra, corners with three equivalent As(2)O4 tetrahedra, edges with three equivalent Co(2)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. In the second Co site, Co(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent As(1)O4 tetrahedra, corners with three equivalent As(2)O4 tetrahedra, edges with three equivalent Co(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form AsO4 tetrahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 54-58°. In the second As site, As(2) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form AsO4 tetrahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 53-58°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ba(1), one Co(1), one Co(2), and one As(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ba(1), one Co(1), one Co(2), and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one As(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one As(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCo2(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.543
_cell_length_b   8.720
_cell_length_c   8.623
_cell_angle_alpha   33.418
_cell_angle_beta   33.728
_cell_angle_gamma   34.161
_symmetry_Int_Tables_number   1
_cell_volume   176.782
_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
  Ba  Ba0  1  1.000  0.001  1.000  1.0
  Co  Co1  1  0.825  0.830  0.840  1.0
  Co  Co2  1  0.173  0.172  0.160  1.0
  As  As3  1  0.436  0.419  0.430  1.0
  As  As4  1  0.564  0.580  0.570  1.0
  O  O5  1  0.553  0.222  0.880  1.0
  O  O6  1  0.206  0.884  0.555  1.0
  O  O7  1  0.871  0.568  0.212  1.0
  O  O8  1  0.450  0.776  0.119  1.0
  O  O9  1  0.795  0.115  0.446  1.0
  O  O10  1  0.359  0.353  0.364  1.0
  O  O11  1  0.639  0.650  0.635  1.0
  O  O12  1  0.130  0.428  0.790  1.0
[/CIF]
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The crystal structure described by BaCo2(AsO4)2 crystallizes in the triclinic P1 space group. Ba(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), one O(8), three equivalent O(6), and three equivalent O(7) atoms to form distorted BaO12 cuboctahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, edges with six equivalent Ba(1)O12 cuboctahedra, edges with three equivalent As(1)O4 tetrahedra, edges with three equivalent As(2)O4 tetrahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-47°. There are two 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(8) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent As(1)O4 tetrahedra, corners with three equivalent As(2)O4 tetrahedra, edges with three equivalent Co(2)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. In the second Co site, Co(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent As(1)O4 tetrahedra, corners with three equivalent As(2)O4 tetrahedra, edges with three equivalent Co(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form AsO4 tetrahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 54-58°. In the second As site, As(2) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form AsO4 tetrahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 53-58°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ba(1), one Co(1), one Co(2), and one As(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ba(1), one Co(1), one Co(2), and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one As(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to three equivalent Ba(1) and one As(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ba(1), one Co(1), one Co(2), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCo2(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.543
_cell_length_b   8.720
_cell_length_c   8.623
_cell_angle_alpha   33.418
_cell_angle_beta   33.728
_cell_angle_gamma   34.161
_symmetry_Int_Tables_number   1
_cell_volume   176.782
_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
  Ba  Ba0  1  1.000  0.001  1.000  1.0
  Co  Co1  1  0.825  0.830  0.840  1.0
  Co  Co2  1  0.173  0.172  0.160  1.0
  As  As3  1  0.436  0.419  0.430  1.0
  As  As4  1  0.564  0.580  0.570  1.0
  O  O5  1  0.553  0.222  0.880  1.0
  O  O6  1  0.206  0.884  0.555  1.0
  O  O7  1  0.871  0.568  0.212  1.0
  O  O8  1  0.450  0.776  0.119  1.0
  O  O9  1  0.795  0.115  0.446  1.0
  O  O10  1  0.359  0.353  0.364  1.0
  O  O11  1  0.639  0.650  0.635  1.0
  O  O12  1  0.130  0.428  0.790  1.0
[/CIF]
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