The compound described by Si3CaC4 is lead oxide-derived structured and crystallizes in the trigonal R3m space group. Ca(1) is bonded in a distorted rectangular see-saw-like geometry to one C(4) and three equivalent C(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one C(1) and three equivalent C(4) atoms to form corner-sharing SiC4 tetrahedra. In the second Si site, Si(2) is bonded to one C(2) and three equivalent C(1) atoms to form corner-sharing SiC4 tetrahedra. In the third Si site, Si(3) is bonded to one C(3) and three equivalent C(2) atoms to form corner-sharing SiC4 tetrahedra. There are four inequivalent C sites. In the first C site, C(1) is bonded to one Si(1) and three equivalent Si(2) atoms to form CSi4 tetrahedra that share corners with three equivalent C(4)CaSi3 tetrahedra, corners with three equivalent C(2)Si4 tetrahedra, and corners with six equivalent C(1)Si4 tetrahedra. In the second C site, C(2) is bonded to one Si(2) and three equivalent Si(3) atoms to form corner-sharing CSi4 tetrahedra. In the third C site, C(3) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Ca(1) and one Si(3) atom. In the fourth C site, C(4) is bonded to one Ca(1) and three equivalent Si(1) atoms to form CCaSi3 tetrahedra that share corners with three equivalent C(1)Si4 tetrahedra and corners with six equivalent C(4)CaSi3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaSi3C4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.150
_cell_length_b   3.150
_cell_length_c   11.636
_cell_angle_alpha   90.000
_cell_angle_beta   82.220
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   98.781
_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  0.488  0.744  0.768  1.0
  Si  Si1  1  0.981  0.991  0.028  1.0
  Si  Si2  1  0.500  0.250  0.250  1.0
  Si  Si3  1  0.019  0.509  0.472  1.0
  C  C4  1  0.868  0.934  0.199  1.0
  C  C5  1  0.389  0.194  0.417  1.0
  C  C6  1  0.911  0.456  0.633  1.0
  C  C7  1  0.344  0.672  0.984  1.0
[/CIF]
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The compound described by Si3CaC4 is lead oxide-derived structured and crystallizes in the trigonal R3m space group. Ca(1) is bonded in a distorted rectangular see-saw-like geometry to one C(4) and three equivalent C(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one C(1) and three equivalent C(4) atoms to form corner-sharing SiC4 tetrahedra. In the second Si site, Si(2) is bonded to one C(2) and three equivalent C(1) atoms to form corner-sharing SiC4 tetrahedra. In the third Si site, Si(3) is bonded to one C(3) and three equivalent C(2) atoms to form corner-sharing SiC4 tetrahedra. There are four inequivalent C sites. In the first C site, C(1) is bonded to one Si(1) and three equivalent Si(2) atoms to form CSi4 tetrahedra that share corners with three equivalent C(4)CaSi3 tetrahedra, corners with three equivalent C(2)Si4 tetrahedra, and corners with six equivalent C(1)Si4 tetrahedra. In the second C site, C(2) is bonded to one Si(2) and three equivalent Si(3) atoms to form corner-sharing CSi4 tetrahedra. In the third C site, C(3) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Ca(1) and one Si(3) atom. In the fourth C site, C(4) is bonded to one Ca(1) and three equivalent Si(1) atoms to form CCaSi3 tetrahedra that share corners with three equivalent C(1)Si4 tetrahedra and corners with six equivalent C(4)CaSi3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaSi3C4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.150
_cell_length_b   3.150
_cell_length_c   11.636
_cell_angle_alpha   90.000
_cell_angle_beta   82.220
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   98.781
_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  0.488  0.744  0.768  1.0
  Si  Si1  1  0.981  0.991  0.028  1.0
  Si  Si2  1  0.500  0.250  0.250  1.0
  Si  Si3  1  0.019  0.509  0.472  1.0
  C  C4  1  0.868  0.934  0.199  1.0
  C  C5  1  0.389  0.194  0.417  1.0
  C  C6  1  0.911  0.456  0.633  1.0
  C  C7  1  0.344  0.672  0.984  1.0
[/CIF]
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