The material described by CaWO2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CaO5 square pyramids that share corners with four equivalent W(2)O6 octahedra, edges with two equivalent Ca(1)O5 square pyramids, and  a faceface with one W(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-62°. In the second Ca site, Ca(2) is bonded in a distorted T-shaped geometry to one O(3) and two equivalent O(2) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second W site, W(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form WO6 octahedra that share corners with four equivalent Ca(1)O5 square pyramids, edges with four equivalent W(2)O6 octahedra, and  a faceface with one Ca(1)O5 square pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one W(2), and two equivalent W(1) atoms to form distorted OCaW3 tetrahedra that share corners with two equivalent O(1)CaW3 tetrahedra,  a cornercorner with one O(4)Ca2W3 trigonal bipyramid, corners with four equivalent O(3)Ca3W2 trigonal bipyramids,  an edgeedge with one O(3)Ca3W2 trigonal bipyramid, and edges with two equivalent O(4)Ca2W3 trigonal bipyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(2) and two equivalent W(2) atoms. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent W(1) atoms to form distorted OCa3W2 trigonal bipyramids that share corners with four equivalent O(1)CaW3 tetrahedra, corners with two equivalent O(4)Ca2W3 trigonal bipyramids,  an edgeedge with one O(1)CaW3 tetrahedra,  an edgeedge with one O(4)Ca2W3 trigonal bipyramid, and edges with two equivalent O(3)Ca3W2 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ca(1) and three equivalent W(2) atoms to form distorted OCa2W3 trigonal bipyramids that share  a cornercorner with one O(1)CaW3 tetrahedra, corners with two equivalent O(3)Ca3W2 trigonal bipyramids, edges with two equivalent O(1)CaW3 tetrahedra,  an edgeedge with one O(3)Ca3W2 trigonal bipyramid, and edges with four equivalent O(4)Ca2W3 trigonal bipyramids. is represented by the CIF file [CIF]
data_CaWO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.366
_cell_length_b   9.366
_cell_length_c   9.955
_cell_angle_alpha   66.519
_cell_angle_beta   66.519
_cell_angle_gamma   20.361
_symmetry_Int_Tables_number   1
_cell_volume   277.837
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.658  0.658  0.310  1.0
  Ca  Ca1  1  0.342  0.342  0.690  1.0
  Ca  Ca2  1  0.989  0.989  0.228  1.0
  Ca  Ca3  1  0.011  0.011  0.772  1.0
  W  W4  1  0.345  0.345  0.996  1.0
  W  W5  1  0.811  0.811  0.355  1.0
  W  W6  1  0.189  0.189  0.645  1.0
  W  W7  1  0.655  0.655  0.004  1.0
  O  O8  1  0.196  0.196  0.856  1.0
  O  O9  1  0.606  0.606  0.685  1.0
  O  O10  1  0.394  0.394  0.315  1.0
  O  O11  1  0.804  0.804  0.144  1.0
  O  O12  1  0.875  0.875  0.828  1.0
  O  O13  1  0.221  0.221  0.406  1.0
  O  O14  1  0.125  0.125  0.172  1.0
  O  O15  1  0.779  0.779  0.594  1.0
[/CIF]
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The material described by CaWO2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CaO5 square pyramids that share corners with four equivalent W(2)O6 octahedra, edges with two equivalent Ca(1)O5 square pyramids, and  a faceface with one W(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-62°. In the second Ca site, Ca(2) is bonded in a distorted T-shaped geometry to one O(3) and two equivalent O(2) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second W site, W(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(4) atoms to form WO6 octahedra that share corners with four equivalent Ca(1)O5 square pyramids, edges with four equivalent W(2)O6 octahedra, and  a faceface with one Ca(1)O5 square pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one W(2), and two equivalent W(1) atoms to form distorted OCaW3 tetrahedra that share corners with two equivalent O(1)CaW3 tetrahedra,  a cornercorner with one O(4)Ca2W3 trigonal bipyramid, corners with four equivalent O(3)Ca3W2 trigonal bipyramids,  an edgeedge with one O(3)Ca3W2 trigonal bipyramid, and edges with two equivalent O(4)Ca2W3 trigonal bipyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(2) and two equivalent W(2) atoms. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent W(1) atoms to form distorted OCa3W2 trigonal bipyramids that share corners with four equivalent O(1)CaW3 tetrahedra, corners with two equivalent O(4)Ca2W3 trigonal bipyramids,  an edgeedge with one O(1)CaW3 tetrahedra,  an edgeedge with one O(4)Ca2W3 trigonal bipyramid, and edges with two equivalent O(3)Ca3W2 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ca(1) and three equivalent W(2) atoms to form distorted OCa2W3 trigonal bipyramids that share  a cornercorner with one O(1)CaW3 tetrahedra, corners with two equivalent O(3)Ca3W2 trigonal bipyramids, edges with two equivalent O(1)CaW3 tetrahedra,  an edgeedge with one O(3)Ca3W2 trigonal bipyramid, and edges with four equivalent O(4)Ca2W3 trigonal bipyramids. is represented by the CIF file [CIF]
data_CaWO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.366
_cell_length_b   9.366
_cell_length_c   9.955
_cell_angle_alpha   66.519
_cell_angle_beta   66.519
_cell_angle_gamma   20.361
_symmetry_Int_Tables_number   1
_cell_volume   277.837
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.658  0.658  0.310  1.0
  Ca  Ca1  1  0.342  0.342  0.690  1.0
  Ca  Ca2  1  0.989  0.989  0.228  1.0
  Ca  Ca3  1  0.011  0.011  0.772  1.0
  W  W4  1  0.345  0.345  0.996  1.0
  W  W5  1  0.811  0.811  0.355  1.0
  W  W6  1  0.189  0.189  0.645  1.0
  W  W7  1  0.655  0.655  0.004  1.0
  O  O8  1  0.196  0.196  0.856  1.0
  O  O9  1  0.606  0.606  0.685  1.0
  O  O10  1  0.394  0.394  0.315  1.0
  O  O11  1  0.804  0.804  0.144  1.0
  O  O12  1  0.875  0.875  0.828  1.0
  O  O13  1  0.221  0.221  0.406  1.0
  O  O14  1  0.125  0.125  0.172  1.0
  O  O15  1  0.779  0.779  0.594  1.0
[/CIF]
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