The compound described by Ca3Co2(Si2O7)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(7), one O(9), two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms. Co(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CoO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(5), one O(8), and two equivalent O(1) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(3)O4 tetrahedra and corners with two equivalent Co(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with two equivalent Co(1)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(8), one O(9), and two equivalent O(2) 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 nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ca(1), one Co(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Co(1), and one Si(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Co(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Co(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Ca(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(2) and two equivalent Si(2) atoms. In the eighth O site, O(8) is bonded in a distorted tetrahedral geometry to two equivalent Ca(1), one Si(1), and one Si(3) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ca(2), two equivalent Ca(1), and one Si(3) atom. is represented by the CIF file [CIF]
data_Ca3Co2(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.834
_cell_length_b   7.834
_cell_length_c   5.122
_cell_angle_alpha   87.662
_cell_angle_beta   87.662
_cell_angle_gamma   89.670
_symmetry_Int_Tables_number   1
_cell_volume   313.866
_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  0.842  0.171  0.494  1.0
  Ca  Ca1  1  0.171  0.842  0.494  1.0
  Ca  Ca2  1  0.650  0.650  0.520  1.0
  Co  Co3  1  0.500  0.005  1.000  1.0
  Co  Co4  1  0.005  0.500  1.000  1.0
  Si  Si5  1  0.134  0.134  0.947  1.0
  Si  Si6  1  0.363  0.646  0.052  1.0
  Si  Si7  1  0.646  0.363  0.052  1.0
  Si  Si8  1  0.857  0.857  0.950  1.0
  O  O9  1  0.316  0.070  0.811  1.0
  O  O10  1  0.683  0.919  0.796  1.0
  O  O11  1  0.605  0.171  0.186  1.0
  O  O12  1  0.420  0.817  0.213  1.0
  O  O13  1  0.070  0.316  0.811  1.0
  O  O14  1  0.171  0.605  0.186  1.0
  O  O15  1  0.817  0.420  0.213  1.0
  O  O16  1  0.919  0.683  0.796  1.0
  O  O17  1  0.112  0.112  0.260  1.0
  O  O18  1  0.371  0.676  0.742  1.0
  O  O19  1  0.500  0.500  0.161  1.0
  O  O20  1  0.998  0.998  0.814  1.0
  O  O21  1  0.676  0.371  0.742  1.0
  O  O22  1  0.845  0.845  0.261  1.0
[/CIF]
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The compound described by Ca3Co2(Si2O7)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(7), one O(9), two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms. Co(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CoO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(5), one O(8), and two equivalent O(1) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(3)O4 tetrahedra and corners with two equivalent Co(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with two equivalent Co(1)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(8), one O(9), and two equivalent O(2) 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 nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ca(1), one Co(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Co(1), and one Si(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Co(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Co(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Ca(2), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(2) and two equivalent Si(2) atoms. In the eighth O site, O(8) is bonded in a distorted tetrahedral geometry to two equivalent Ca(1), one Si(1), and one Si(3) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ca(2), two equivalent Ca(1), and one Si(3) atom. is represented by the CIF file [CIF]
data_Ca3Co2(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.834
_cell_length_b   7.834
_cell_length_c   5.122
_cell_angle_alpha   87.662
_cell_angle_beta   87.662
_cell_angle_gamma   89.670
_symmetry_Int_Tables_number   1
_cell_volume   313.866
_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  0.842  0.171  0.494  1.0
  Ca  Ca1  1  0.171  0.842  0.494  1.0
  Ca  Ca2  1  0.650  0.650  0.520  1.0
  Co  Co3  1  0.500  0.005  1.000  1.0
  Co  Co4  1  0.005  0.500  1.000  1.0
  Si  Si5  1  0.134  0.134  0.947  1.0
  Si  Si6  1  0.363  0.646  0.052  1.0
  Si  Si7  1  0.646  0.363  0.052  1.0
  Si  Si8  1  0.857  0.857  0.950  1.0
  O  O9  1  0.316  0.070  0.811  1.0
  O  O10  1  0.683  0.919  0.796  1.0
  O  O11  1  0.605  0.171  0.186  1.0
  O  O12  1  0.420  0.817  0.213  1.0
  O  O13  1  0.070  0.316  0.811  1.0
  O  O14  1  0.171  0.605  0.186  1.0
  O  O15  1  0.817  0.420  0.213  1.0
  O  O16  1  0.919  0.683  0.796  1.0
  O  O17  1  0.112  0.112  0.260  1.0
  O  O18  1  0.371  0.676  0.742  1.0
  O  O19  1  0.500  0.500  0.161  1.0
  O  O20  1  0.998  0.998  0.814  1.0
  O  O21  1  0.676  0.371  0.742  1.0
  O  O22  1  0.845  0.845  0.261  1.0
[/CIF]
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