The crystal structure described by Sr4CaSi3 crystallizes in the tetragonal I4/mcm space group. Sr(1) is bonded in a 5-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. Ca(1) 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 six equivalent Sr(1), two 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 Sr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr4CaSi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.763
_cell_length_b   9.763
_cell_length_c   9.763
_cell_angle_alpha   132.037
_cell_angle_beta   132.037
_cell_angle_gamma   70.170
_symmetry_Int_Tables_number   1
_cell_volume   503.206
_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
  Sr  Sr0  1  0.820  0.320  0.861  1.0
  Sr  Sr1  1  0.180  0.680  0.139  1.0
  Sr  Sr2  1  0.459  0.959  0.139  1.0
  Sr  Sr3  1  0.320  0.459  0.500  1.0
  Sr  Sr4  1  0.041  0.180  0.500  1.0
  Sr  Sr5  1  0.541  0.041  0.861  1.0
  Sr  Sr6  1  0.680  0.541  0.500  1.0
  Sr  Sr7  1  0.959  0.820  0.500  1.0
  Ca  Ca8  1  0.000  0.000  0.000  1.0
  Ca  Ca9  1  0.500  0.500  0.000  1.0
  Si  Si10  1  0.111  0.611  0.721  1.0
  Si  Si11  1  0.889  0.389  0.279  1.0
  Si  Si12  1  0.611  0.889  0.500  1.0
  Si  Si13  1  0.389  0.111  0.500  1.0
  Si  Si14  1  0.250  0.250  0.000  1.0
  Si  Si15  1  0.750  0.750  0.000  1.0
[/CIF]
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The crystal structure described by Sr4CaSi3 crystallizes in the tetragonal I4/mcm space group. Sr(1) is bonded in a 5-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. Ca(1) 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 six equivalent Sr(1), two 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 Sr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr4CaSi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.763
_cell_length_b   9.763
_cell_length_c   9.763
_cell_angle_alpha   132.037
_cell_angle_beta   132.037
_cell_angle_gamma   70.170
_symmetry_Int_Tables_number   1
_cell_volume   503.206
_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
  Sr  Sr0  1  0.820  0.320  0.861  1.0
  Sr  Sr1  1  0.180  0.680  0.139  1.0
  Sr  Sr2  1  0.459  0.959  0.139  1.0
  Sr  Sr3  1  0.320  0.459  0.500  1.0
  Sr  Sr4  1  0.041  0.180  0.500  1.0
  Sr  Sr5  1  0.541  0.041  0.861  1.0
  Sr  Sr6  1  0.680  0.541  0.500  1.0
  Sr  Sr7  1  0.959  0.820  0.500  1.0
  Ca  Ca8  1  0.000  0.000  0.000  1.0
  Ca  Ca9  1  0.500  0.500  0.000  1.0
  Si  Si10  1  0.111  0.611  0.721  1.0
  Si  Si11  1  0.889  0.389  0.279  1.0
  Si  Si12  1  0.611  0.889  0.500  1.0
  Si  Si13  1  0.389  0.111  0.500  1.0
  Si  Si14  1  0.250  0.250  0.000  1.0
  Si  Si15  1  0.750  0.750  0.000  1.0
[/CIF]
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