The structure described by Ca3(PO4)2 crystallizes in the trigonal R-3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. In the second Ca site, Ca(2) is bonded in a 10-coordinate geometry to one O(2) and nine equivalent O(1) atoms. P(1) is bonded in a tetrahedral geometry to one O(2) and three equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ca(1), three equivalent Ca(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Ca(2) and one P(1) atom. is represented by the CIF card [CIF]
data_Ca3(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.896
_cell_length_b   6.896
_cell_length_c   6.896
_cell_angle_alpha   44.544
_cell_angle_beta   44.544
_cell_angle_gamma   44.544
_symmetry_Int_Tables_number   1
_cell_volume   146.736
_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
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.203  0.203  0.203  1.0
  Ca  Ca2  1  0.797  0.797  0.797  1.0
  P  P3  1  0.405  0.405  0.405  1.0
  P  P4  1  0.595  0.595  0.595  1.0
  O  O5  1  0.727  0.727  0.247  1.0
  O  O6  1  0.727  0.247  0.727  1.0
  O  O7  1  0.247  0.727  0.727  1.0
  O  O8  1  0.753  0.273  0.273  1.0
  O  O9  1  0.273  0.273  0.753  1.0
  O  O10  1  0.323  0.323  0.323  1.0
  O  O11  1  0.677  0.677  0.677  1.0
  O  O12  1  0.273  0.753  0.273  1.0
[/CIF]
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The structure described by Ca3(PO4)2 crystallizes in the trigonal R-3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. In the second Ca site, Ca(2) is bonded in a 10-coordinate geometry to one O(2) and nine equivalent O(1) atoms. P(1) is bonded in a tetrahedral geometry to one O(2) and three equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ca(1), three equivalent Ca(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Ca(2) and one P(1) atom. is represented by the CIF card [CIF]
data_Ca3(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.896
_cell_length_b   6.896
_cell_length_c   6.896
_cell_angle_alpha   44.544
_cell_angle_beta   44.544
_cell_angle_gamma   44.544
_symmetry_Int_Tables_number   1
_cell_volume   146.736
_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
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.203  0.203  0.203  1.0
  Ca  Ca2  1  0.797  0.797  0.797  1.0
  P  P3  1  0.405  0.405  0.405  1.0
  P  P4  1  0.595  0.595  0.595  1.0
  O  O5  1  0.727  0.727  0.247  1.0
  O  O6  1  0.727  0.247  0.727  1.0
  O  O7  1  0.247  0.727  0.727  1.0
  O  O8  1  0.753  0.273  0.273  1.0
  O  O9  1  0.273  0.273  0.753  1.0
  O  O10  1  0.323  0.323  0.323  1.0
  O  O11  1  0.677  0.677  0.677  1.0
  O  O12  1  0.273  0.753  0.273  1.0
[/CIF]
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