The structure described by Ca(OH)2 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded in a 7-coordinate geometry to one H(2), three equivalent O(1), and three equivalent O(2) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one Ca(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to three equivalent Ca(1) and one H(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to three equivalent Ca(1) and one H(2) atom. is represented by the CIF card [CIF]
data_Ca(HO)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.395
_cell_length_b   6.039
_cell_length_c   5.952
_cell_angle_alpha   90.000
_cell_angle_beta   104.639
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.649
_cell_formula_units_Z   4
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  0.314  0.430  0.688  1.0
  Ca  Ca1  1  0.686  0.930  0.812  1.0
  Ca  Ca2  1  0.686  0.570  0.312  1.0
  Ca  Ca3  1  0.314  0.070  0.188  1.0
  H  H4  1  0.132  0.997  0.700  1.0
  H  H5  1  0.868  0.497  0.800  1.0
  H  H6  1  0.868  0.003  0.300  1.0
  H  H7  1  0.132  0.503  0.200  1.0
  H  H8  1  0.221  0.722  0.920  1.0
  H  H9  1  0.779  0.222  0.580  1.0
  H  H10  1  0.779  0.278  0.080  1.0
  H  H11  1  0.221  0.778  0.420  1.0
  O  O12  1  0.074  0.122  0.777  1.0
  O  O13  1  0.926  0.622  0.723  1.0
  O  O14  1  0.926  0.878  0.223  1.0
  O  O15  1  0.074  0.378  0.277  1.0
  O  O16  1  0.405  0.739  0.994  1.0
  O  O17  1  0.595  0.239  0.506  1.0
  O  O18  1  0.595  0.261  0.006  1.0
  O  O19  1  0.405  0.761  0.494  1.0
[/CIF]
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The structure described by Ca(OH)2 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded in a 7-coordinate geometry to one H(2), three equivalent O(1), and three equivalent O(2) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one Ca(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to three equivalent Ca(1) and one H(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to three equivalent Ca(1) and one H(2) atom. is represented by the CIF card [CIF]
data_Ca(HO)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.395
_cell_length_b   6.039
_cell_length_c   5.952
_cell_angle_alpha   90.000
_cell_angle_beta   104.639
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.649
_cell_formula_units_Z   4
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  0.314  0.430  0.688  1.0
  Ca  Ca1  1  0.686  0.930  0.812  1.0
  Ca  Ca2  1  0.686  0.570  0.312  1.0
  Ca  Ca3  1  0.314  0.070  0.188  1.0
  H  H4  1  0.132  0.997  0.700  1.0
  H  H5  1  0.868  0.497  0.800  1.0
  H  H6  1  0.868  0.003  0.300  1.0
  H  H7  1  0.132  0.503  0.200  1.0
  H  H8  1  0.221  0.722  0.920  1.0
  H  H9  1  0.779  0.222  0.580  1.0
  H  H10  1  0.779  0.278  0.080  1.0
  H  H11  1  0.221  0.778  0.420  1.0
  O  O12  1  0.074  0.122  0.777  1.0
  O  O13  1  0.926  0.622  0.723  1.0
  O  O14  1  0.926  0.878  0.223  1.0
  O  O15  1  0.074  0.378  0.277  1.0
  O  O16  1  0.405  0.739  0.994  1.0
  O  O17  1  0.595  0.239  0.506  1.0
  O  O18  1  0.595  0.261  0.006  1.0
  O  O19  1  0.405  0.761  0.494  1.0
[/CIF]
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