The material described by Ca3LaSi8 is hexagonal omega structure-derived structured and crystallizes in the tetragonal P-4m2 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four Si(4,4) and eight equivalent Si(2) atoms to form a mixture of edge and face-sharing CaSi12 cuboctahedra. In the second Ca site, Ca(2) is bonded to two equivalent Si(1), two equivalent Si(2), four equivalent Si(3), and four equivalent Si(4) atoms to form CaSi12 cuboctahedra that share edges with four equivalent Ca(1)Si12 cuboctahedra, edges with four equivalent Ca(2)Si12 cuboctahedra, edges with four equivalent La(1)Si12 cuboctahedra, faces with two equivalent Ca(1)Si12 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with four equivalent Ca(2)Si12 cuboctahedra. In the third Ca site, Ca(2) is bonded to two equivalent Si(1), two equivalent Si(2), four equivalent Si(3), and four equivalent Si(4) atoms to form CaSi12 cuboctahedra that share edges with four equivalent Ca(1)Si12 cuboctahedra, edges with four equivalent Ca(2)Si12 cuboctahedra, edges with four equivalent La(1)Si12 cuboctahedra, faces with two equivalent Ca(1)Si12 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with four equivalent Ca(2)Si12 cuboctahedra. La(1) is bonded to four Si(3,3) and eight Si(1,1) atoms to form LaSi12 cuboctahedra that share edges with four equivalent La(1)Si12 cuboctahedra; edges with eight Ca(2,2)Si12 cuboctahedra; faces with four Ca(2,2)Si12 cuboctahedra; and faces with four equivalent La(1)Si12 cuboctahedra. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), four equivalent La(1), one Si(1), and two equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Ca(2), four equivalent Ca(1), one Si(2), and two equivalent Si(4) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Ca(2), two equivalent La(1), one Si(4), and two equivalent Si(1) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Ca(1), four equivalent Ca(2), one Si(3), and two equivalent Si(2) atoms. In the fifth Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), four equivalent La(1), one Si(1), and two equivalent Si(3) atoms. In the sixth Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Ca(2), two equivalent La(1), one Si(4), and two equivalent Si(1) atoms. In the seventh Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Ca(1), four equivalent Ca(2), one Si(3), and two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3LaSi8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.314
_cell_length_b   4.314
_cell_length_c   13.506
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   251.327
_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  0.000  0.000  0.500  1.0
  Ca  Ca1  1  0.500  0.000  0.749  1.0
  Ca  Ca2  1  0.000  0.500  0.251  1.0
  La  La3  1  0.500  0.500  0.000  1.0
  Si  Si4  1  0.000  0.000  0.915  1.0
  Si  Si5  1  0.500  0.500  0.415  1.0
  Si  Si6  1  0.000  0.500  0.835  1.0
  Si  Si7  1  0.500  0.000  0.335  1.0
  Si  Si8  1  0.000  0.000  0.085  1.0
  Si  Si9  1  0.500  0.500  0.585  1.0
  Si  Si10  1  0.500  0.000  0.165  1.0
  Si  Si11  1  0.000  0.500  0.665  1.0
[/CIF]
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The material described by Ca3LaSi8 is hexagonal omega structure-derived structured and crystallizes in the tetragonal P-4m2 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four Si(4,4) and eight equivalent Si(2) atoms to form a mixture of edge and face-sharing CaSi12 cuboctahedra. In the second Ca site, Ca(2) is bonded to two equivalent Si(1), two equivalent Si(2), four equivalent Si(3), and four equivalent Si(4) atoms to form CaSi12 cuboctahedra that share edges with four equivalent Ca(1)Si12 cuboctahedra, edges with four equivalent Ca(2)Si12 cuboctahedra, edges with four equivalent La(1)Si12 cuboctahedra, faces with two equivalent Ca(1)Si12 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with four equivalent Ca(2)Si12 cuboctahedra. In the third Ca site, Ca(2) is bonded to two equivalent Si(1), two equivalent Si(2), four equivalent Si(3), and four equivalent Si(4) atoms to form CaSi12 cuboctahedra that share edges with four equivalent Ca(1)Si12 cuboctahedra, edges with four equivalent Ca(2)Si12 cuboctahedra, edges with four equivalent La(1)Si12 cuboctahedra, faces with two equivalent Ca(1)Si12 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with four equivalent Ca(2)Si12 cuboctahedra. La(1) is bonded to four Si(3,3) and eight Si(1,1) atoms to form LaSi12 cuboctahedra that share edges with four equivalent La(1)Si12 cuboctahedra; edges with eight Ca(2,2)Si12 cuboctahedra; faces with four Ca(2,2)Si12 cuboctahedra; and faces with four equivalent La(1)Si12 cuboctahedra. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), four equivalent La(1), one Si(1), and two equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Ca(2), four equivalent Ca(1), one Si(2), and two equivalent Si(4) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Ca(2), two equivalent La(1), one Si(4), and two equivalent Si(1) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Ca(1), four equivalent Ca(2), one Si(3), and two equivalent Si(2) atoms. In the fifth Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ca(2), four equivalent La(1), one Si(1), and two equivalent Si(3) atoms. In the sixth Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Ca(2), two equivalent La(1), one Si(4), and two equivalent Si(1) atoms. In the seventh Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Ca(1), four equivalent Ca(2), one Si(3), and two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3LaSi8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.314
_cell_length_b   4.314
_cell_length_c   13.506
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   251.327
_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  0.000  0.000  0.500  1.0
  Ca  Ca1  1  0.500  0.000  0.749  1.0
  Ca  Ca2  1  0.000  0.500  0.251  1.0
  La  La3  1  0.500  0.500  0.000  1.0
  Si  Si4  1  0.000  0.000  0.915  1.0
  Si  Si5  1  0.500  0.500  0.415  1.0
  Si  Si6  1  0.000  0.500  0.835  1.0
  Si  Si7  1  0.500  0.000  0.335  1.0
  Si  Si8  1  0.000  0.000  0.085  1.0
  Si  Si9  1  0.500  0.500  0.585  1.0
  Si  Si10  1  0.500  0.000  0.165  1.0
  Si  Si11  1  0.000  0.500  0.665  1.0
[/CIF]
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