The material structure described by CaNb2O4 crystallizes in the orthorhombic Pbcm space group. Ca(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted CaO6 pentagonal pyramids that share corners with four equivalent Nb(1)O6 pentagonal pyramids, corners with five equivalent Nb(2)O6 pentagonal pyramids,  an edgeedge with one Nb(2)O6 pentagonal pyramid, edges with two equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Nb(1)O6 pentagonal pyramids, and  a faceface with one Nb(2)O6 pentagonal pyramid. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NbO6 pentagonal pyramids that share corners with four equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Nb(1)O6 pentagonal pyramids, and edges with four equivalent Nb(2)O6 pentagonal pyramids. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted NbO6 pentagonal pyramids that share corners with five equivalent Ca(1)O6 pentagonal pyramids,  an edgeedge with one Ca(1)O6 pentagonal pyramid, edges with two equivalent Nb(2)O6 pentagonal pyramids, edges with four equivalent Nb(1)O6 pentagonal pyramids, and  a faceface with one Ca(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Nb(2), and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Nb(2), and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1), one Nb(1), and two equivalent Nb(2) atoms to form a mixture of corner, face, and edge-sharing OCa2Nb3 trigonal bipyramids. is represented by the CIF file [CIF]
data_CaNb2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.093
_cell_length_b   5.884
_cell_length_c   11.955
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   358.304
_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  0.691  0.250  0.496  1.0
  Ca  Ca1  1  0.691  0.750  0.004  1.0
  Ca  Ca2  1  0.309  0.750  0.504  1.0
  Ca  Ca3  1  0.309  0.250  0.996  1.0
  Nb  Nb4  1  0.844  0.000  0.250  1.0
  Nb  Nb5  1  0.156  0.500  0.750  1.0
  Nb  Nb6  1  0.156  0.000  0.750  1.0
  Nb  Nb7  1  0.844  0.500  0.250  1.0
  Nb  Nb8  1  0.659  0.750  0.746  1.0
  Nb  Nb9  1  0.659  0.250  0.754  1.0
  Nb  Nb10  1  0.341  0.250  0.254  1.0
  Nb  Nb11  1  0.341  0.750  0.246  1.0
  O  O12  1  0.986  0.750  0.857  1.0
  O  O13  1  0.986  0.250  0.643  1.0
  O  O14  1  0.014  0.250  0.143  1.0
  O  O15  1  0.014  0.750  0.357  1.0
  O  O16  1  0.994  0.750  0.639  1.0
  O  O17  1  0.994  0.250  0.861  1.0
  O  O18  1  0.006  0.250  0.361  1.0
  O  O19  1  0.006  0.750  0.139  1.0
  O  O20  1  0.508  0.996  0.363  1.0
  O  O21  1  0.508  0.004  0.137  1.0
  O  O22  1  0.492  0.496  0.637  1.0
  O  O23  1  0.492  0.504  0.863  1.0
  O  O24  1  0.508  0.496  0.137  1.0
  O  O25  1  0.508  0.504  0.363  1.0
  O  O26  1  0.492  0.996  0.863  1.0
  O  O27  1  0.492  0.004  0.637  1.0
[/CIF]
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The material structure described by CaNb2O4 crystallizes in the orthorhombic Pbcm space group. Ca(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted CaO6 pentagonal pyramids that share corners with four equivalent Nb(1)O6 pentagonal pyramids, corners with five equivalent Nb(2)O6 pentagonal pyramids,  an edgeedge with one Nb(2)O6 pentagonal pyramid, edges with two equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Nb(1)O6 pentagonal pyramids, and  a faceface with one Nb(2)O6 pentagonal pyramid. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NbO6 pentagonal pyramids that share corners with four equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Nb(1)O6 pentagonal pyramids, and edges with four equivalent Nb(2)O6 pentagonal pyramids. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted NbO6 pentagonal pyramids that share corners with five equivalent Ca(1)O6 pentagonal pyramids,  an edgeedge with one Ca(1)O6 pentagonal pyramid, edges with two equivalent Nb(2)O6 pentagonal pyramids, edges with four equivalent Nb(1)O6 pentagonal pyramids, and  a faceface with one Ca(1)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Nb(2), and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Nb(2), and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1), one Nb(1), and two equivalent Nb(2) atoms to form a mixture of corner, face, and edge-sharing OCa2Nb3 trigonal bipyramids. is represented by the CIF file [CIF]
data_CaNb2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.093
_cell_length_b   5.884
_cell_length_c   11.955
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   358.304
_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  0.691  0.250  0.496  1.0
  Ca  Ca1  1  0.691  0.750  0.004  1.0
  Ca  Ca2  1  0.309  0.750  0.504  1.0
  Ca  Ca3  1  0.309  0.250  0.996  1.0
  Nb  Nb4  1  0.844  0.000  0.250  1.0
  Nb  Nb5  1  0.156  0.500  0.750  1.0
  Nb  Nb6  1  0.156  0.000  0.750  1.0
  Nb  Nb7  1  0.844  0.500  0.250  1.0
  Nb  Nb8  1  0.659  0.750  0.746  1.0
  Nb  Nb9  1  0.659  0.250  0.754  1.0
  Nb  Nb10  1  0.341  0.250  0.254  1.0
  Nb  Nb11  1  0.341  0.750  0.246  1.0
  O  O12  1  0.986  0.750  0.857  1.0
  O  O13  1  0.986  0.250  0.643  1.0
  O  O14  1  0.014  0.250  0.143  1.0
  O  O15  1  0.014  0.750  0.357  1.0
  O  O16  1  0.994  0.750  0.639  1.0
  O  O17  1  0.994  0.250  0.861  1.0
  O  O18  1  0.006  0.250  0.361  1.0
  O  O19  1  0.006  0.750  0.139  1.0
  O  O20  1  0.508  0.996  0.363  1.0
  O  O21  1  0.508  0.004  0.137  1.0
  O  O22  1  0.492  0.496  0.637  1.0
  O  O23  1  0.492  0.504  0.863  1.0
  O  O24  1  0.508  0.496  0.137  1.0
  O  O25  1  0.508  0.504  0.363  1.0
  O  O26  1  0.492  0.996  0.863  1.0
  O  O27  1  0.492  0.004  0.637  1.0
[/CIF]
.