The compound described by Ca3NbO6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(1), three equivalent O(2), and three equivalent O(3) atoms. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CaO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-42°. Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with six equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-42°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ca(2), two equivalent Ca(1), and one Nb(1) atom to form distorted corner-sharing OCa3Nb tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(2), three equivalent Ca(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ca(2), three equivalent Ca(1), and one Nb(1) atom. is represented by the CIF file [CIF]
data_Ca3NbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.942
_cell_length_b   5.687
_cell_length_c   9.893
_cell_angle_alpha   55.379
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   275.132
_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
  Ca  Ca0  1  0.058  0.726  0.758  1.0
  Ca  Ca1  1  0.942  0.274  0.242  1.0
  Ca  Ca2  1  0.558  0.274  0.742  1.0
  Ca  Ca3  1  0.442  0.726  0.258  1.0
  Ca  Ca4  1  0.500  0.500  0.000  1.0
  Ca  Ca5  1  0.000  0.500  0.500  1.0
  Nb  Nb6  1  0.500  0.000  0.500  1.0
  Nb  Nb7  1  0.000  0.000  0.000  1.0
  O  O8  1  0.441  0.893  0.730  1.0
  O  O9  1  0.559  0.107  0.270  1.0
  O  O10  1  0.941  0.107  0.770  1.0
  O  O11  1  0.059  0.893  0.230  1.0
  O  O12  1  0.784  0.756  0.574  1.0
  O  O13  1  0.216  0.244  0.426  1.0
  O  O14  1  0.284  0.244  0.926  1.0
  O  O15  1  0.716  0.756  0.074  1.0
  O  O16  1  0.323  0.654  0.556  1.0
  O  O17  1  0.677  0.346  0.444  1.0
  O  O18  1  0.823  0.346  0.944  1.0
  O  O19  1  0.177  0.654  0.056  1.0
[/CIF]
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The compound described by Ca3NbO6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(1), three equivalent O(2), and three equivalent O(3) atoms. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CaO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-42°. Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with six equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-42°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ca(2), two equivalent Ca(1), and one Nb(1) atom to form distorted corner-sharing OCa3Nb tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(2), three equivalent Ca(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ca(2), three equivalent Ca(1), and one Nb(1) atom. is represented by the CIF file [CIF]
data_Ca3NbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.942
_cell_length_b   5.687
_cell_length_c   9.893
_cell_angle_alpha   55.379
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   275.132
_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
  Ca  Ca0  1  0.058  0.726  0.758  1.0
  Ca  Ca1  1  0.942  0.274  0.242  1.0
  Ca  Ca2  1  0.558  0.274  0.742  1.0
  Ca  Ca3  1  0.442  0.726  0.258  1.0
  Ca  Ca4  1  0.500  0.500  0.000  1.0
  Ca  Ca5  1  0.000  0.500  0.500  1.0
  Nb  Nb6  1  0.500  0.000  0.500  1.0
  Nb  Nb7  1  0.000  0.000  0.000  1.0
  O  O8  1  0.441  0.893  0.730  1.0
  O  O9  1  0.559  0.107  0.270  1.0
  O  O10  1  0.941  0.107  0.770  1.0
  O  O11  1  0.059  0.893  0.230  1.0
  O  O12  1  0.784  0.756  0.574  1.0
  O  O13  1  0.216  0.244  0.426  1.0
  O  O14  1  0.284  0.244  0.926  1.0
  O  O15  1  0.716  0.756  0.074  1.0
  O  O16  1  0.323  0.654  0.556  1.0
  O  O17  1  0.677  0.346  0.444  1.0
  O  O18  1  0.823  0.346  0.944  1.0
  O  O19  1  0.177  0.654  0.056  1.0
[/CIF]
.