The compound described by CaC4O4 crystallizes in the tetragonal I4_1/amd space group. Ca(1) is bonded to eight equivalent O(1) atoms to form distorted edge-sharing CaO8 hexagonal bipyramids. There are two inequivalent C sites. In the first C site, C(2) is bonded in a distorted bent 120 degrees geometry to one C(1) and two equivalent O(1) atoms. In the second C site, C(1) is bonded in a linear geometry to one C(1) and one C(2) atom. O(1) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one C(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca(CO)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.982
_cell_length_b   7.136
_cell_length_c   6.982
_cell_angle_alpha   119.292
_cell_angle_beta   90.000
_cell_angle_gamma   119.292
_symmetry_Int_Tables_number   1
_cell_volume   251.160
_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  0.500  0.000  0.500  1.0
  Ca  Ca1  1  0.750  0.500  0.250  1.0
  C  C2  1  0.059  0.118  0.059  1.0
  C  C3  1  0.309  0.618  0.809  1.0
  C  C4  1  0.191  0.382  0.691  1.0
  C  C5  1  0.941  0.882  0.941  1.0
  C  C6  1  0.199  0.398  0.199  1.0
  C  C7  1  0.449  0.898  0.949  1.0
  C  C8  1  0.051  0.102  0.551  1.0
  C  C9  1  0.801  0.602  0.801  1.0
  O  O10  1  0.418  0.516  0.258  1.0
  O  O11  1  0.508  0.016  0.848  1.0
  O  O12  1  0.508  0.016  0.168  1.0
  O  O13  1  0.098  0.516  0.258  1.0
  O  O14  1  0.832  0.984  0.492  1.0
  O  O15  1  0.742  0.484  0.902  1.0
  O  O16  1  0.742  0.484  0.582  1.0
  O  O17  1  0.152  0.984  0.492  1.0
[/CIF]
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The compound described by CaC4O4 crystallizes in the tetragonal I4_1/amd space group. Ca(1) is bonded to eight equivalent O(1) atoms to form distorted edge-sharing CaO8 hexagonal bipyramids. There are two inequivalent C sites. In the first C site, C(2) is bonded in a distorted bent 120 degrees geometry to one C(1) and two equivalent O(1) atoms. In the second C site, C(1) is bonded in a linear geometry to one C(1) and one C(2) atom. O(1) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one C(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca(CO)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.982
_cell_length_b   7.136
_cell_length_c   6.982
_cell_angle_alpha   119.292
_cell_angle_beta   90.000
_cell_angle_gamma   119.292
_symmetry_Int_Tables_number   1
_cell_volume   251.160
_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  0.500  0.000  0.500  1.0
  Ca  Ca1  1  0.750  0.500  0.250  1.0
  C  C2  1  0.059  0.118  0.059  1.0
  C  C3  1  0.309  0.618  0.809  1.0
  C  C4  1  0.191  0.382  0.691  1.0
  C  C5  1  0.941  0.882  0.941  1.0
  C  C6  1  0.199  0.398  0.199  1.0
  C  C7  1  0.449  0.898  0.949  1.0
  C  C8  1  0.051  0.102  0.551  1.0
  C  C9  1  0.801  0.602  0.801  1.0
  O  O10  1  0.418  0.516  0.258  1.0
  O  O11  1  0.508  0.016  0.848  1.0
  O  O12  1  0.508  0.016  0.168  1.0
  O  O13  1  0.098  0.516  0.258  1.0
  O  O14  1  0.832  0.984  0.492  1.0
  O  O15  1  0.742  0.484  0.902  1.0
  O  O16  1  0.742  0.484  0.582  1.0
  O  O17  1  0.152  0.984  0.492  1.0
[/CIF]
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