The crystal structure described by Ca2CoSi2O7 crystallizes in the tetragonal P-42_1m space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(2), and four equivalent O(3) atoms. Co(1) is bonded to four equivalent O(3) atoms to form CoO4 tetrahedra that share corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with two equivalent Co(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted tetrahedral geometry to two equivalent Ca(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Ca(1) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Co(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca2CoSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.063
_cell_length_b   7.909
_cell_length_c   7.909
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   316.764
_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  0.499  0.170  0.670  1.0
  Ca  Ca1  1  0.499  0.830  0.330  1.0
  Ca  Ca2  1  0.501  0.670  0.830  1.0
  Ca  Ca3  1  0.501  0.330  0.170  1.0
  Co  Co4  1  0.000  0.500  0.500  1.0
  Co  Co5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.184  0.500  0.000  1.0
  O  O7  1  0.816  1.000  0.500  1.0
  O  O8  1  0.251  0.857  0.643  1.0
  O  O9  1  0.749  0.643  0.143  1.0
  O  O10  1  0.749  0.357  0.857  1.0
  O  O11  1  0.251  0.143  0.357  1.0
  O  O12  1  0.777  0.686  0.582  1.0
  O  O13  1  0.777  0.314  0.418  1.0
  O  O14  1  0.223  0.418  0.686  1.0
  O  O15  1  0.223  0.582  0.314  1.0
  O  O16  1  0.777  0.918  0.814  1.0
  O  O17  1  0.223  0.814  0.082  1.0
  O  O18  1  0.223  0.186  0.918  1.0
  O  O19  1  0.777  0.082  0.186  1.0
  Si  Si20  1  0.932  0.859  0.641  1.0
  Si  Si21  1  0.068  0.641  0.141  1.0
  Si  Si22  1  0.068  0.359  0.859  1.0
  Si  Si23  1  0.932  0.141  0.359  1.0
[/CIF]
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The crystal structure described by Ca2CoSi2O7 crystallizes in the tetragonal P-42_1m space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(2), and four equivalent O(3) atoms. Co(1) is bonded to four equivalent O(3) atoms to form CoO4 tetrahedra that share corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with two equivalent Co(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted tetrahedral geometry to two equivalent Ca(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Ca(1) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Co(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca2CoSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.063
_cell_length_b   7.909
_cell_length_c   7.909
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   316.764
_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  0.499  0.170  0.670  1.0
  Ca  Ca1  1  0.499  0.830  0.330  1.0
  Ca  Ca2  1  0.501  0.670  0.830  1.0
  Ca  Ca3  1  0.501  0.330  0.170  1.0
  Co  Co4  1  0.000  0.500  0.500  1.0
  Co  Co5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.184  0.500  0.000  1.0
  O  O7  1  0.816  1.000  0.500  1.0
  O  O8  1  0.251  0.857  0.643  1.0
  O  O9  1  0.749  0.643  0.143  1.0
  O  O10  1  0.749  0.357  0.857  1.0
  O  O11  1  0.251  0.143  0.357  1.0
  O  O12  1  0.777  0.686  0.582  1.0
  O  O13  1  0.777  0.314  0.418  1.0
  O  O14  1  0.223  0.418  0.686  1.0
  O  O15  1  0.223  0.582  0.314  1.0
  O  O16  1  0.777  0.918  0.814  1.0
  O  O17  1  0.223  0.814  0.082  1.0
  O  O18  1  0.223  0.186  0.918  1.0
  O  O19  1  0.777  0.082  0.186  1.0
  Si  Si20  1  0.932  0.859  0.641  1.0
  Si  Si21  1  0.068  0.641  0.141  1.0
  Si  Si22  1  0.068  0.359  0.859  1.0
  Si  Si23  1  0.932  0.141  0.359  1.0
[/CIF]
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