The crystal structure described by SiPO4(OH) crystallizes in the monoclinic P2_1/c space group. Si(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form SiO6 octahedra that share corners with two equivalent Si(1)O6 octahedra and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. P(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-40°. H(1) is bonded in a single-bond geometry to one O(2) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Si(1) and one H(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiPHO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.001
_cell_length_b   6.920
_cell_length_c   6.955
_cell_angle_alpha   60.005
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   291.826
_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
  Si  Si0  1  0.250  0.251  0.500  1.0
  Si  Si1  1  0.250  0.251  0.000  1.0
  Si  Si2  1  0.750  0.749  0.500  1.0
  Si  Si3  1  0.750  0.749  1.000  1.0
  P  P4  1  0.883  0.251  0.250  1.0
  P  P5  1  0.617  0.251  0.750  1.0
  P  P6  1  0.117  0.749  0.750  1.0
  P  P7  1  0.383  0.749  0.250  1.0
  H  H8  1  0.026  0.216  0.768  1.0
  H  H9  1  0.474  0.216  0.268  1.0
  H  H10  1  0.974  0.784  0.232  1.0
  H  H11  1  0.526  0.784  0.732  1.0
  O  O12  1  0.011  0.251  0.430  1.0
  O  O13  1  0.489  0.251  0.930  1.0
  O  O14  1  0.989  0.749  0.570  1.0
  O  O15  1  0.511  0.749  0.070  1.0
  O  O16  1  0.164  0.247  0.752  1.0
  O  O17  1  0.336  0.247  0.252  1.0
  O  O18  1  0.836  0.753  0.248  1.0
  O  O19  1  0.664  0.753  0.748  1.0
  O  O20  1  0.748  0.453  0.148  1.0
  O  O21  1  0.752  0.453  0.648  1.0
  O  O22  1  0.252  0.547  0.852  1.0
  O  O23  1  0.248  0.547  0.352  1.0
  O  O24  1  0.745  0.050  0.351  1.0
  O  O25  1  0.755  0.050  0.851  1.0
  O  O26  1  0.255  0.950  0.649  1.0
  O  O27  1  0.245  0.950  0.149  1.0
  O  O28  1  0.010  0.246  0.072  1.0
  O  O29  1  0.490  0.246  0.572  1.0
  O  O30  1  0.990  0.754  0.928  1.0
  O  O31  1  0.510  0.754  0.428  1.0
[/CIF]
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The crystal structure described by SiPO4(OH) crystallizes in the monoclinic P2_1/c space group. Si(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form SiO6 octahedra that share corners with two equivalent Si(1)O6 octahedra and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. P(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with four equivalent Si(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-40°. H(1) is bonded in a single-bond geometry to one O(2) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Si(1) and one H(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SiPHO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.001
_cell_length_b   6.920
_cell_length_c   6.955
_cell_angle_alpha   60.005
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   291.826
_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
  Si  Si0  1  0.250  0.251  0.500  1.0
  Si  Si1  1  0.250  0.251  0.000  1.0
  Si  Si2  1  0.750  0.749  0.500  1.0
  Si  Si3  1  0.750  0.749  1.000  1.0
  P  P4  1  0.883  0.251  0.250  1.0
  P  P5  1  0.617  0.251  0.750  1.0
  P  P6  1  0.117  0.749  0.750  1.0
  P  P7  1  0.383  0.749  0.250  1.0
  H  H8  1  0.026  0.216  0.768  1.0
  H  H9  1  0.474  0.216  0.268  1.0
  H  H10  1  0.974  0.784  0.232  1.0
  H  H11  1  0.526  0.784  0.732  1.0
  O  O12  1  0.011  0.251  0.430  1.0
  O  O13  1  0.489  0.251  0.930  1.0
  O  O14  1  0.989  0.749  0.570  1.0
  O  O15  1  0.511  0.749  0.070  1.0
  O  O16  1  0.164  0.247  0.752  1.0
  O  O17  1  0.336  0.247  0.252  1.0
  O  O18  1  0.836  0.753  0.248  1.0
  O  O19  1  0.664  0.753  0.748  1.0
  O  O20  1  0.748  0.453  0.148  1.0
  O  O21  1  0.752  0.453  0.648  1.0
  O  O22  1  0.252  0.547  0.852  1.0
  O  O23  1  0.248  0.547  0.352  1.0
  O  O24  1  0.745  0.050  0.351  1.0
  O  O25  1  0.755  0.050  0.851  1.0
  O  O26  1  0.255  0.950  0.649  1.0
  O  O27  1  0.245  0.950  0.149  1.0
  O  O28  1  0.010  0.246  0.072  1.0
  O  O29  1  0.490  0.246  0.572  1.0
  O  O30  1  0.990  0.754  0.928  1.0
  O  O31  1  0.510  0.754  0.428  1.0
[/CIF]
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