The material described by Ca3Al2P4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to two equivalent P(2) and four equivalent P(1) atoms. In the second Ca site, Ca(2) is bonded to two equivalent P(1) and four equivalent P(2) atoms to form distorted CaP6 octahedra that share corners with four equivalent Al(1)P4 tetrahedra, edges with two equivalent Ca(2)P6 octahedra, and edges with four equivalent Al(1)P4 tetrahedra. Al(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form AlP4 tetrahedra that share corners with two equivalent Ca(2)P6 octahedra, corners with two equivalent Al(1)P4 tetrahedra, edges with two equivalent Ca(2)P6 octahedra, and  an edgeedge with one Al(1)P4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-59°. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 7-coordinate geometry to one Ca(2), four equivalent Ca(1), and two equivalent Al(1) atoms. In the second P site, P(2) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_Ca3(AlP2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.009
_cell_length_b   8.009
_cell_length_c   6.455
_cell_angle_alpha   89.690
_cell_angle_beta   89.690
_cell_angle_gamma   75.662
_symmetry_Int_Tables_number   1
_cell_volume   401.214
_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  0.751  0.008  0.971  1.0
  Ca  Ca1  1  0.992  0.249  0.529  1.0
  Ca  Ca2  1  0.249  0.992  0.029  1.0
  Ca  Ca3  1  0.008  0.751  0.471  1.0
  Ca  Ca4  1  0.599  0.401  0.250  1.0
  Ca  Ca5  1  0.401  0.599  0.750  1.0
  Al  Al6  1  0.580  0.828  0.411  1.0
  Al  Al7  1  0.172  0.420  0.089  1.0
  Al  Al8  1  0.420  0.172  0.589  1.0
  Al  Al9  1  0.828  0.580  0.911  1.0
  P  P10  1  0.714  0.058  0.476  1.0
  P  P11  1  0.942  0.286  0.024  1.0
  P  P12  1  0.286  0.942  0.524  1.0
  P  P13  1  0.058  0.714  0.976  1.0
  P  P14  1  0.571  0.742  0.064  1.0
  P  P15  1  0.258  0.429  0.436  1.0
  P  P16  1  0.429  0.258  0.936  1.0
  P  P17  1  0.742  0.571  0.564  1.0
[/CIF]
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The material described by Ca3Al2P4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to two equivalent P(2) and four equivalent P(1) atoms. In the second Ca site, Ca(2) is bonded to two equivalent P(1) and four equivalent P(2) atoms to form distorted CaP6 octahedra that share corners with four equivalent Al(1)P4 tetrahedra, edges with two equivalent Ca(2)P6 octahedra, and edges with four equivalent Al(1)P4 tetrahedra. Al(1) is bonded to two equivalent P(1) and two equivalent P(2) atoms to form AlP4 tetrahedra that share corners with two equivalent Ca(2)P6 octahedra, corners with two equivalent Al(1)P4 tetrahedra, edges with two equivalent Ca(2)P6 octahedra, and  an edgeedge with one Al(1)P4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-59°. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 7-coordinate geometry to one Ca(2), four equivalent Ca(1), and two equivalent Al(1) atoms. In the second P site, P(2) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), and two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_Ca3(AlP2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.009
_cell_length_b   8.009
_cell_length_c   6.455
_cell_angle_alpha   89.690
_cell_angle_beta   89.690
_cell_angle_gamma   75.662
_symmetry_Int_Tables_number   1
_cell_volume   401.214
_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  0.751  0.008  0.971  1.0
  Ca  Ca1  1  0.992  0.249  0.529  1.0
  Ca  Ca2  1  0.249  0.992  0.029  1.0
  Ca  Ca3  1  0.008  0.751  0.471  1.0
  Ca  Ca4  1  0.599  0.401  0.250  1.0
  Ca  Ca5  1  0.401  0.599  0.750  1.0
  Al  Al6  1  0.580  0.828  0.411  1.0
  Al  Al7  1  0.172  0.420  0.089  1.0
  Al  Al8  1  0.420  0.172  0.589  1.0
  Al  Al9  1  0.828  0.580  0.911  1.0
  P  P10  1  0.714  0.058  0.476  1.0
  P  P11  1  0.942  0.286  0.024  1.0
  P  P12  1  0.286  0.942  0.524  1.0
  P  P13  1  0.058  0.714  0.976  1.0
  P  P14  1  0.571  0.742  0.064  1.0
  P  P15  1  0.258  0.429  0.436  1.0
  P  P16  1  0.429  0.258  0.936  1.0
  P  P17  1  0.742  0.571  0.564  1.0
[/CIF]
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