The compound described by BaSiP4(HO7)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(6), two equivalent O(7), and four equivalent O(1) atoms. Si(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form SiO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Si(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-42°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Si(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. H(1) is bonded in a linear geometry to one O(6) and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Si(1), and one P(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 120 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one P(2), and one H(1) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Ba(1), one P(2), and one H(1) atom. is represented by the CIF file [CIF]
data_BaSiP4(HO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.672
_cell_length_b   6.696
_cell_length_c   9.180
_cell_angle_alpha   75.217
_cell_angle_beta   85.565
_cell_angle_gamma   75.347
_symmetry_Int_Tables_number   1
_cell_volume   268.589
_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
  Ba  Ba0  1  0.000  0.000  0.000  1.0
  Si  Si1  1  0.000  0.000  0.500  1.0
  P  P2  1  0.414  0.167  0.666  1.0
  P  P3  1  0.586  0.833  0.334  1.0
  P  P4  1  0.096  0.562  0.738  1.0
  P  P5  1  0.904  0.438  0.262  1.0
  H  H6  1  0.546  0.542  0.830  1.0
  H  H7  1  0.454  0.458  0.170  1.0
  O  O8  1  0.510  0.088  0.828  1.0
  O  O9  1  0.490  0.912  0.172  1.0
  O  O10  1  0.152  0.075  0.647  1.0
  O  O11  1  0.848  0.925  0.353  1.0
  O  O12  1  0.353  0.852  0.459  1.0
  O  O13  1  0.647  0.148  0.541  1.0
  O  O14  1  0.287  0.424  0.629  1.0
  O  O15  1  0.713  0.576  0.371  1.0
  O  O16  1  0.069  0.228  0.364  1.0
  O  O17  1  0.931  0.772  0.636  1.0
  O  O18  1  0.118  0.555  0.167  1.0
  O  O19  1  0.882  0.445  0.833  1.0
  O  O20  1  0.320  0.607  0.837  1.0
  O  O21  1  0.680  0.393  0.163  1.0
[/CIF]
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The compound described by BaSiP4(HO7)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(6), two equivalent O(7), and four equivalent O(1) atoms. Si(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form SiO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Si(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-42°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Si(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. H(1) is bonded in a linear geometry to one O(6) and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Si(1), and one P(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 120 degrees geometry to one P(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one P(2), and one H(1) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Ba(1), one P(2), and one H(1) atom. is represented by the CIF file [CIF]
data_BaSiP4(HO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.672
_cell_length_b   6.696
_cell_length_c   9.180
_cell_angle_alpha   75.217
_cell_angle_beta   85.565
_cell_angle_gamma   75.347
_symmetry_Int_Tables_number   1
_cell_volume   268.589
_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
  Ba  Ba0  1  0.000  0.000  0.000  1.0
  Si  Si1  1  0.000  0.000  0.500  1.0
  P  P2  1  0.414  0.167  0.666  1.0
  P  P3  1  0.586  0.833  0.334  1.0
  P  P4  1  0.096  0.562  0.738  1.0
  P  P5  1  0.904  0.438  0.262  1.0
  H  H6  1  0.546  0.542  0.830  1.0
  H  H7  1  0.454  0.458  0.170  1.0
  O  O8  1  0.510  0.088  0.828  1.0
  O  O9  1  0.490  0.912  0.172  1.0
  O  O10  1  0.152  0.075  0.647  1.0
  O  O11  1  0.848  0.925  0.353  1.0
  O  O12  1  0.353  0.852  0.459  1.0
  O  O13  1  0.647  0.148  0.541  1.0
  O  O14  1  0.287  0.424  0.629  1.0
  O  O15  1  0.713  0.576  0.371  1.0
  O  O16  1  0.069  0.228  0.364  1.0
  O  O17  1  0.931  0.772  0.636  1.0
  O  O18  1  0.118  0.555  0.167  1.0
  O  O19  1  0.882  0.445  0.833  1.0
  O  O20  1  0.320  0.607  0.837  1.0
  O  O21  1  0.680  0.393  0.163  1.0
[/CIF]
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