The crystal structure described by Ca3Y is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Ca(1), four equivalent Ca(2), and four equivalent Y(1) atoms to form CaCa8Y4 cuboctahedra that share corners with twelve equivalent Ca(1)Ca8Y4 cuboctahedra, edges with eight equivalent Ca(1)Ca8Y4 cuboctahedra, edges with eight equivalent Ca(2)Ca8Y4 cuboctahedra, edges with eight equivalent Y(1)Ca12 cuboctahedra, faces with four equivalent Ca(2)Ca8Y4 cuboctahedra, faces with four equivalent Y(1)Ca12 cuboctahedra, and faces with ten equivalent Ca(1)Ca8Y4 cuboctahedra. In the second Ca site, Ca(2) is bonded to eight equivalent Ca(1) and four equivalent Y(1) atoms to form CaCa8Y4 cuboctahedra that share corners with four equivalent Ca(2)Ca8Y4 cuboctahedra, corners with eight equivalent Y(1)Ca12 cuboctahedra, edges with eight equivalent Ca(2)Ca8Y4 cuboctahedra, edges with sixteen equivalent Ca(1)Ca8Y4 cuboctahedra, faces with four equivalent Ca(2)Ca8Y4 cuboctahedra, faces with six equivalent Y(1)Ca12 cuboctahedra, and faces with eight equivalent Ca(1)Ca8Y4 cuboctahedra. Y(1) is bonded to four equivalent Ca(2) and eight equivalent Ca(1) atoms to form YCa12 cuboctahedra that share corners with four equivalent Y(1)Ca12 cuboctahedra, corners with eight equivalent Ca(2)Ca8Y4 cuboctahedra, edges with eight equivalent Y(1)Ca12 cuboctahedra, edges with sixteen equivalent Ca(1)Ca8Y4 cuboctahedra, faces with four equivalent Y(1)Ca12 cuboctahedra, faces with six equivalent Ca(2)Ca8Y4 cuboctahedra, and faces with eight equivalent Ca(1)Ca8Y4 cuboctahedra. is represented by the CIF file [CIF]
data_Ca3Y
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.660
_cell_length_b   6.660
_cell_length_c   6.660
_cell_angle_alpha   132.273
_cell_angle_beta   132.273
_cell_angle_gamma   69.799
_symmetry_Int_Tables_number   1
_cell_volume   158.593
_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  0.750  0.250  0.500  1.0
  Ca  Ca1  1  0.250  0.750  0.500  1.0
  Ca  Ca2  1  0.500  0.500  0.000  1.0
  Y  Y3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Ca3Y is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Ca(1), four equivalent Ca(2), and four equivalent Y(1) atoms to form CaCa8Y4 cuboctahedra that share corners with twelve equivalent Ca(1)Ca8Y4 cuboctahedra, edges with eight equivalent Ca(1)Ca8Y4 cuboctahedra, edges with eight equivalent Ca(2)Ca8Y4 cuboctahedra, edges with eight equivalent Y(1)Ca12 cuboctahedra, faces with four equivalent Ca(2)Ca8Y4 cuboctahedra, faces with four equivalent Y(1)Ca12 cuboctahedra, and faces with ten equivalent Ca(1)Ca8Y4 cuboctahedra. In the second Ca site, Ca(2) is bonded to eight equivalent Ca(1) and four equivalent Y(1) atoms to form CaCa8Y4 cuboctahedra that share corners with four equivalent Ca(2)Ca8Y4 cuboctahedra, corners with eight equivalent Y(1)Ca12 cuboctahedra, edges with eight equivalent Ca(2)Ca8Y4 cuboctahedra, edges with sixteen equivalent Ca(1)Ca8Y4 cuboctahedra, faces with four equivalent Ca(2)Ca8Y4 cuboctahedra, faces with six equivalent Y(1)Ca12 cuboctahedra, and faces with eight equivalent Ca(1)Ca8Y4 cuboctahedra. Y(1) is bonded to four equivalent Ca(2) and eight equivalent Ca(1) atoms to form YCa12 cuboctahedra that share corners with four equivalent Y(1)Ca12 cuboctahedra, corners with eight equivalent Ca(2)Ca8Y4 cuboctahedra, edges with eight equivalent Y(1)Ca12 cuboctahedra, edges with sixteen equivalent Ca(1)Ca8Y4 cuboctahedra, faces with four equivalent Y(1)Ca12 cuboctahedra, faces with six equivalent Ca(2)Ca8Y4 cuboctahedra, and faces with eight equivalent Ca(1)Ca8Y4 cuboctahedra. is represented by the CIF file [CIF]
data_Ca3Y
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.660
_cell_length_b   6.660
_cell_length_c   6.660
_cell_angle_alpha   132.273
_cell_angle_beta   132.273
_cell_angle_gamma   69.799
_symmetry_Int_Tables_number   1
_cell_volume   158.593
_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  0.750  0.250  0.500  1.0
  Ca  Ca1  1  0.250  0.750  0.500  1.0
  Ca  Ca2  1  0.500  0.500  0.000  1.0
  Y  Y3  1  0.000  0.000  0.000  1.0
[/CIF]
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