The material structure described by Ca5Si3 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent Si(2) and three equivalent Si(1) atoms to form a mixture of distorted corner, edge, and face-sharing CaSi5 trigonal bipyramids. In the second Ca site, Ca(2) is bonded in a square co-planar geometry to four equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), six equivalent Ca(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to eight equivalent Ca(1) atoms. is represented by the CIF card [CIF]
data_Ca5Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.654
_cell_length_b   7.654
_cell_length_c   9.158
_cell_angle_alpha   114.700
_cell_angle_beta   114.700
_cell_angle_gamma   90.004
_symmetry_Int_Tables_number   1
_cell_volume   432.785
_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  0.180  0.042  0.722  1.0
  Ca  Ca1  1  0.042  0.542  0.722  1.0
  Ca  Ca2  1  0.680  0.180  0.722  1.0
  Ca  Ca3  1  0.958  0.458  0.278  1.0
  Ca  Ca4  1  0.542  0.680  0.722  1.0
  Ca  Ca5  1  0.820  0.958  0.278  1.0
  Ca  Ca6  1  0.458  0.320  0.278  1.0
  Ca  Ca7  1  0.320  0.820  0.278  1.0
  Ca  Ca8  1  0.500  0.500  0.000  1.0
  Ca  Ca9  1  0.000  0.000  0.000  1.0
  Si  Si10  1  0.612  0.112  0.000  1.0
  Si  Si11  1  0.888  0.612  0.000  1.0
  Si  Si12  1  0.112  0.388  1.000  1.0
  Si  Si13  1  0.388  0.888  1.000  1.0
  Si  Si14  1  0.750  0.750  0.500  1.0
  Si  Si15  1  0.250  0.250  0.500  1.0
[/CIF]
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The material structure described by Ca5Si3 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent Si(2) and three equivalent Si(1) atoms to form a mixture of distorted corner, edge, and face-sharing CaSi5 trigonal bipyramids. In the second Ca site, Ca(2) is bonded in a square co-planar geometry to four equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), six equivalent Ca(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to eight equivalent Ca(1) atoms. is represented by the CIF card [CIF]
data_Ca5Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.654
_cell_length_b   7.654
_cell_length_c   9.158
_cell_angle_alpha   114.700
_cell_angle_beta   114.700
_cell_angle_gamma   90.004
_symmetry_Int_Tables_number   1
_cell_volume   432.785
_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  0.180  0.042  0.722  1.0
  Ca  Ca1  1  0.042  0.542  0.722  1.0
  Ca  Ca2  1  0.680  0.180  0.722  1.0
  Ca  Ca3  1  0.958  0.458  0.278  1.0
  Ca  Ca4  1  0.542  0.680  0.722  1.0
  Ca  Ca5  1  0.820  0.958  0.278  1.0
  Ca  Ca6  1  0.458  0.320  0.278  1.0
  Ca  Ca7  1  0.320  0.820  0.278  1.0
  Ca  Ca8  1  0.500  0.500  0.000  1.0
  Ca  Ca9  1  0.000  0.000  0.000  1.0
  Si  Si10  1  0.612  0.112  0.000  1.0
  Si  Si11  1  0.888  0.612  0.000  1.0
  Si  Si12  1  0.112  0.388  1.000  1.0
  Si  Si13  1  0.388  0.888  1.000  1.0
  Si  Si14  1  0.750  0.750  0.500  1.0
  Si  Si15  1  0.250  0.250  0.500  1.0
[/CIF]
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