The structure described by Ca8Al3 crystallizes in the triclinic P-1 space group. There are eight inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 4-coordinate geometry to one Al(2), one Al(4), and two equivalent Al(3) atoms. In the second Ca site, Ca(2) is bonded in a 2-coordinate geometry to one Al(1), one Al(3), and two equivalent Al(4) atoms. In the third Ca site, Ca(3) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and two equivalent Al(3) atoms. In the fourth Ca site, Ca(4) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and two equivalent Al(4) atoms. In the fifth Ca site, Ca(5) is bonded in a distorted bent 120 degrees geometry to one Al(4) and two equivalent Al(3) atoms. In the sixth Ca site, Ca(6) is bonded in a 2-coordinate geometry to one Al(1), one Al(3), and two equivalent Al(4) atoms. In the seventh Ca site, Ca(7) is bonded in a distorted trigonal non-coplanar geometry to one Al(2), one Al(3), and one Al(4) atom. In the eighth Ca site, Ca(8) is bonded in a distorted trigonal non-coplanar geometry to one Al(2), one Al(3), and one Al(4) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a body-centered cubic geometry to two equivalent Ca(2), two equivalent Ca(3), two equivalent Ca(4), and two equivalent Ca(6) atoms. In the second Al site, Al(2) is bonded in a distorted q6 geometry to two equivalent Ca(1), two equivalent Ca(3), two equivalent Ca(4), two equivalent Ca(7), and two equivalent Ca(8) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Ca(2), one Ca(6), one Ca(7), one Ca(8), two equivalent Ca(1), two equivalent Ca(3), and two equivalent Ca(5) atoms. In the fourth Al site, Al(4) is bonded in a 10-coordinate geometry to one Ca(1), one Ca(5), one Ca(7), one Ca(8), two equivalent Ca(2), two equivalent Ca(4), and two equivalent Ca(6) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca8Al3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.471
_cell_length_b   9.554
_cell_length_c   9.624
_cell_angle_alpha   99.083
_cell_angle_beta   100.967
_cell_angle_gamma   119.704
_symmetry_Int_Tables_number   1
_cell_volume   709.385
_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  0.532  0.701  0.650  1.0
  Ca  Ca1  1  0.468  0.299  0.350  1.0
  Ca  Ca2  1  0.079  0.231  0.106  1.0
  Ca  Ca3  1  0.921  0.769  0.894  1.0
  Ca  Ca4  1  0.879  0.401  0.650  1.0
  Ca  Ca5  1  0.121  0.599  0.350  1.0
  Ca  Ca6  1  0.332  0.878  0.109  1.0
  Ca  Ca7  1  0.668  0.122  0.891  1.0
  Ca  Ca8  1  0.960  0.061  0.670  1.0
  Ca  Ca9  1  0.040  0.939  0.330  1.0
  Ca  Ca10  1  0.702  0.498  0.110  1.0
  Ca  Ca11  1  0.298  0.502  0.890  1.0
  Ca  Ca12  1  0.775  0.153  0.300  1.0
  Ca  Ca13  1  0.225  0.847  0.700  1.0
  Ca  Ca14  1  0.546  0.712  0.298  1.0
  Ca  Ca15  1  0.454  0.288  0.702  1.0
  Al  Al16  1  0.000  0.500  0.000  1.0
  Al  Al17  1  0.500  0.000  0.500  1.0
  Al  Al18  1  0.173  0.337  0.500  1.0
  Al  Al19  1  0.827  0.663  0.500  1.0
  Al  Al20  1  0.676  0.841  0.027  1.0
  Al  Al21  1  0.324  0.159  0.973  1.0
[/CIF]
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The structure described by Ca8Al3 crystallizes in the triclinic P-1 space group. There are eight inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 4-coordinate geometry to one Al(2), one Al(4), and two equivalent Al(3) atoms. In the second Ca site, Ca(2) is bonded in a 2-coordinate geometry to one Al(1), one Al(3), and two equivalent Al(4) atoms. In the third Ca site, Ca(3) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and two equivalent Al(3) atoms. In the fourth Ca site, Ca(4) is bonded in a 3-coordinate geometry to one Al(1), one Al(2), and two equivalent Al(4) atoms. In the fifth Ca site, Ca(5) is bonded in a distorted bent 120 degrees geometry to one Al(4) and two equivalent Al(3) atoms. In the sixth Ca site, Ca(6) is bonded in a 2-coordinate geometry to one Al(1), one Al(3), and two equivalent Al(4) atoms. In the seventh Ca site, Ca(7) is bonded in a distorted trigonal non-coplanar geometry to one Al(2), one Al(3), and one Al(4) atom. In the eighth Ca site, Ca(8) is bonded in a distorted trigonal non-coplanar geometry to one Al(2), one Al(3), and one Al(4) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a body-centered cubic geometry to two equivalent Ca(2), two equivalent Ca(3), two equivalent Ca(4), and two equivalent Ca(6) atoms. In the second Al site, Al(2) is bonded in a distorted q6 geometry to two equivalent Ca(1), two equivalent Ca(3), two equivalent Ca(4), two equivalent Ca(7), and two equivalent Ca(8) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Ca(2), one Ca(6), one Ca(7), one Ca(8), two equivalent Ca(1), two equivalent Ca(3), and two equivalent Ca(5) atoms. In the fourth Al site, Al(4) is bonded in a 10-coordinate geometry to one Ca(1), one Ca(5), one Ca(7), one Ca(8), two equivalent Ca(2), two equivalent Ca(4), and two equivalent Ca(6) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca8Al3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.471
_cell_length_b   9.554
_cell_length_c   9.624
_cell_angle_alpha   99.083
_cell_angle_beta   100.967
_cell_angle_gamma   119.704
_symmetry_Int_Tables_number   1
_cell_volume   709.385
_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  0.532  0.701  0.650  1.0
  Ca  Ca1  1  0.468  0.299  0.350  1.0
  Ca  Ca2  1  0.079  0.231  0.106  1.0
  Ca  Ca3  1  0.921  0.769  0.894  1.0
  Ca  Ca4  1  0.879  0.401  0.650  1.0
  Ca  Ca5  1  0.121  0.599  0.350  1.0
  Ca  Ca6  1  0.332  0.878  0.109  1.0
  Ca  Ca7  1  0.668  0.122  0.891  1.0
  Ca  Ca8  1  0.960  0.061  0.670  1.0
  Ca  Ca9  1  0.040  0.939  0.330  1.0
  Ca  Ca10  1  0.702  0.498  0.110  1.0
  Ca  Ca11  1  0.298  0.502  0.890  1.0
  Ca  Ca12  1  0.775  0.153  0.300  1.0
  Ca  Ca13  1  0.225  0.847  0.700  1.0
  Ca  Ca14  1  0.546  0.712  0.298  1.0
  Ca  Ca15  1  0.454  0.288  0.702  1.0
  Al  Al16  1  0.000  0.500  0.000  1.0
  Al  Al17  1  0.500  0.000  0.500  1.0
  Al  Al18  1  0.173  0.337  0.500  1.0
  Al  Al19  1  0.827  0.663  0.500  1.0
  Al  Al20  1  0.676  0.841  0.027  1.0
  Al  Al21  1  0.324  0.159  0.973  1.0
[/CIF]
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