The structure described by Ca2Cu2Si3(HO3)4 crystallizes in the monoclinic P2_1/m space group. Ca(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted square co-planar geometry to one O(4), two equivalent O(3), and two equivalent O(7) atoms. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(7) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(7) atom. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Cu(1), and one Si(2) atom. In the second O site, O(5) is bonded in a distorted water-like geometry to two equivalent Ca(1), one Si(1), and one H(1) atom. In the third O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Ca(1) and one Si(1) atom. In the fourth O site, O(7) is bonded in a distorted single-bond geometry to one Ca(1), one Cu(1), one Cu(2), and one H(2) atom. In the fifth O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Cu(2), and one Si(2) atom. In the sixth O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the seventh O site, O(3) is bonded in a distorted T-shaped geometry to one Cu(1), one Cu(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca2Cu2Si3(HO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.711
_cell_length_b   5.569
_cell_length_c   7.477
_cell_angle_alpha   82.857
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   566.498
_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  0.384  0.941  0.809  1.0
  Ca  Ca1  1  0.884  0.059  0.191  1.0
  Ca  Ca2  1  0.616  0.059  0.191  1.0
  Ca  Ca3  1  0.116  0.941  0.809  1.0
  Cu  Cu4  1  0.250  0.778  0.446  1.0
  Cu  Cu5  1  0.750  0.222  0.554  1.0
  Cu  Cu6  1  0.250  0.278  0.473  1.0
  Cu  Cu7  1  0.750  0.722  0.527  1.0
  Si  Si8  1  0.412  0.488  0.227  1.0
  Si  Si9  1  0.912  0.512  0.773  1.0
  Si  Si10  1  0.588  0.512  0.773  1.0
  Si  Si11  1  0.088  0.488  0.227  1.0
  Si  Si12  1  0.250  0.443  0.922  1.0
  Si  Si13  1  0.750  0.557  0.078  1.0
  H  H14  1  0.432  0.884  0.235  1.0
  H  H15  1  0.932  0.116  0.765  1.0
  H  H16  1  0.568  0.116  0.765  1.0
  H  H17  1  0.068  0.884  0.235  1.0
  H  H18  1  0.403  0.088  0.419  1.0
  H  H19  1  0.903  0.912  0.581  1.0
  H  H20  1  0.597  0.912  0.581  1.0
  H  H21  1  0.097  0.088  0.419  1.0
  O  O22  1  0.250  0.204  0.820  1.0
  O  O23  1  0.750  0.796  0.180  1.0
  O  O24  1  0.348  0.436  0.051  1.0
  O  O25  1  0.848  0.564  0.949  1.0
  O  O26  1  0.652  0.564  0.949  1.0
  O  O27  1  0.152  0.436  0.051  1.0
  O  O28  1  0.345  0.533  0.402  1.0
  O  O29  1  0.845  0.467  0.598  1.0
  O  O30  1  0.655  0.467  0.598  1.0
  O  O31  1  0.155  0.533  0.402  1.0
  O  O32  1  0.250  0.700  0.795  1.0
  O  O33  1  0.750  0.300  0.205  1.0
  O  O34  1  0.461  0.769  0.161  1.0
  O  O35  1  0.961  0.231  0.839  1.0
  O  O36  1  0.539  0.231  0.839  1.0
  O  O37  1  0.039  0.769  0.161  1.0
  O  O38  1  0.515  0.735  0.725  1.0
  O  O39  1  0.015  0.265  0.275  1.0
  O  O40  1  0.485  0.265  0.275  1.0
  O  O41  1  0.985  0.735  0.725  1.0
  O  O42  1  0.348  0.022  0.499  1.0
  O  O43  1  0.848  0.978  0.501  1.0
  O  O44  1  0.652  0.978  0.501  1.0
  O  O45  1  0.152  0.022  0.499  1.0
[/CIF]
.
The structure described by Ca2Cu2Si3(HO3)4 crystallizes in the monoclinic P2_1/m space group. Ca(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted square co-planar geometry to one O(4), two equivalent O(3), and two equivalent O(7) atoms. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(7) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(7) atom. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Cu(1), and one Si(2) atom. In the second O site, O(5) is bonded in a distorted water-like geometry to two equivalent Ca(1), one Si(1), and one H(1) atom. In the third O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Ca(1) and one Si(1) atom. In the fourth O site, O(7) is bonded in a distorted single-bond geometry to one Ca(1), one Cu(1), one Cu(2), and one H(2) atom. In the fifth O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Cu(2), and one Si(2) atom. In the sixth O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the seventh O site, O(3) is bonded in a distorted T-shaped geometry to one Cu(1), one Cu(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca2Cu2Si3(HO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.711
_cell_length_b   5.569
_cell_length_c   7.477
_cell_angle_alpha   82.857
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   566.498
_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  0.384  0.941  0.809  1.0
  Ca  Ca1  1  0.884  0.059  0.191  1.0
  Ca  Ca2  1  0.616  0.059  0.191  1.0
  Ca  Ca3  1  0.116  0.941  0.809  1.0
  Cu  Cu4  1  0.250  0.778  0.446  1.0
  Cu  Cu5  1  0.750  0.222  0.554  1.0
  Cu  Cu6  1  0.250  0.278  0.473  1.0
  Cu  Cu7  1  0.750  0.722  0.527  1.0
  Si  Si8  1  0.412  0.488  0.227  1.0
  Si  Si9  1  0.912  0.512  0.773  1.0
  Si  Si10  1  0.588  0.512  0.773  1.0
  Si  Si11  1  0.088  0.488  0.227  1.0
  Si  Si12  1  0.250  0.443  0.922  1.0
  Si  Si13  1  0.750  0.557  0.078  1.0
  H  H14  1  0.432  0.884  0.235  1.0
  H  H15  1  0.932  0.116  0.765  1.0
  H  H16  1  0.568  0.116  0.765  1.0
  H  H17  1  0.068  0.884  0.235  1.0
  H  H18  1  0.403  0.088  0.419  1.0
  H  H19  1  0.903  0.912  0.581  1.0
  H  H20  1  0.597  0.912  0.581  1.0
  H  H21  1  0.097  0.088  0.419  1.0
  O  O22  1  0.250  0.204  0.820  1.0
  O  O23  1  0.750  0.796  0.180  1.0
  O  O24  1  0.348  0.436  0.051  1.0
  O  O25  1  0.848  0.564  0.949  1.0
  O  O26  1  0.652  0.564  0.949  1.0
  O  O27  1  0.152  0.436  0.051  1.0
  O  O28  1  0.345  0.533  0.402  1.0
  O  O29  1  0.845  0.467  0.598  1.0
  O  O30  1  0.655  0.467  0.598  1.0
  O  O31  1  0.155  0.533  0.402  1.0
  O  O32  1  0.250  0.700  0.795  1.0
  O  O33  1  0.750  0.300  0.205  1.0
  O  O34  1  0.461  0.769  0.161  1.0
  O  O35  1  0.961  0.231  0.839  1.0
  O  O36  1  0.539  0.231  0.839  1.0
  O  O37  1  0.039  0.769  0.161  1.0
  O  O38  1  0.515  0.735  0.725  1.0
  O  O39  1  0.015  0.265  0.275  1.0
  O  O40  1  0.485  0.265  0.275  1.0
  O  O41  1  0.985  0.735  0.725  1.0
  O  O42  1  0.348  0.022  0.499  1.0
  O  O43  1  0.848  0.978  0.501  1.0
  O  O44  1  0.652  0.978  0.501  1.0
  O  O45  1  0.152  0.022  0.499  1.0
[/CIF]
.