The material described by Hg2P2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to one O(1), one O(2), one O(3), one O(7), and two equivalent O(6) atoms to form HgO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, corners with three equivalent Hg(2)O5 trigonal bipyramids, and  an edgeedge with one Hg(1)O6 octahedra. In the second Hg site, Hg(2) is bonded to one O(2), one O(3), one O(7), and two equivalent O(4) atoms to form distorted HgO5 trigonal bipyramids that share corners with three equivalent Hg(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one Hg(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 63-77°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Hg(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Hg(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 44-57°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Hg(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Hg(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 47-55°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Hg(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Hg(1), one Hg(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Hg(1), one Hg(2), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Hg(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Hg(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Hg(1), one Hg(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hg2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.746
_cell_length_b   6.887
_cell_length_c   7.052
_cell_angle_alpha   78.667
_cell_angle_beta   66.865
_cell_angle_gamma   80.222
_symmetry_Int_Tables_number   1
_cell_volume   293.845
_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
  Hg  Hg0  1  0.102  0.173  0.246  1.0
  Hg  Hg1  1  0.898  0.827  0.754  1.0
  Hg  Hg2  1  0.303  0.318  0.629  1.0
  Hg  Hg3  1  0.697  0.682  0.371  1.0
  P  P4  1  0.215  0.659  0.262  1.0
  P  P5  1  0.785  0.341  0.738  1.0
  P  P6  1  0.361  0.869  0.830  1.0
  P  P7  1  0.639  0.131  0.170  1.0
  O  O8  1  0.229  0.759  0.765  1.0
  O  O9  1  0.771  0.241  0.235  1.0
  O  O10  1  0.084  0.518  0.231  1.0
  O  O11  1  0.916  0.482  0.769  1.0
  O  O12  1  0.254  0.079  0.884  1.0
  O  O13  1  0.746  0.921  0.116  1.0
  O  O14  1  0.370  0.558  0.370  1.0
  O  O15  1  0.630  0.442  0.630  1.0
  O  O16  1  0.617  0.250  0.959  1.0
  O  O17  1  0.383  0.750  0.041  1.0
  O  O18  1  0.935  0.168  0.636  1.0
  O  O19  1  0.065  0.832  0.364  1.0
  O  O20  1  0.407  0.122  0.325  1.0
  O  O21  1  0.593  0.878  0.675  1.0
[/CIF]
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The material described by Hg2P2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to one O(1), one O(2), one O(3), one O(7), and two equivalent O(6) atoms to form HgO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, corners with three equivalent Hg(2)O5 trigonal bipyramids, and  an edgeedge with one Hg(1)O6 octahedra. In the second Hg site, Hg(2) is bonded to one O(2), one O(3), one O(7), and two equivalent O(4) atoms to form distorted HgO5 trigonal bipyramids that share corners with three equivalent Hg(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one Hg(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 63-77°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Hg(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Hg(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 44-57°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Hg(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Hg(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 47-55°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Hg(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Hg(1), one Hg(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Hg(1), one Hg(2), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Hg(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Hg(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Hg(1), one Hg(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hg2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.746
_cell_length_b   6.887
_cell_length_c   7.052
_cell_angle_alpha   78.667
_cell_angle_beta   66.865
_cell_angle_gamma   80.222
_symmetry_Int_Tables_number   1
_cell_volume   293.845
_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
  Hg  Hg0  1  0.102  0.173  0.246  1.0
  Hg  Hg1  1  0.898  0.827  0.754  1.0
  Hg  Hg2  1  0.303  0.318  0.629  1.0
  Hg  Hg3  1  0.697  0.682  0.371  1.0
  P  P4  1  0.215  0.659  0.262  1.0
  P  P5  1  0.785  0.341  0.738  1.0
  P  P6  1  0.361  0.869  0.830  1.0
  P  P7  1  0.639  0.131  0.170  1.0
  O  O8  1  0.229  0.759  0.765  1.0
  O  O9  1  0.771  0.241  0.235  1.0
  O  O10  1  0.084  0.518  0.231  1.0
  O  O11  1  0.916  0.482  0.769  1.0
  O  O12  1  0.254  0.079  0.884  1.0
  O  O13  1  0.746  0.921  0.116  1.0
  O  O14  1  0.370  0.558  0.370  1.0
  O  O15  1  0.630  0.442  0.630  1.0
  O  O16  1  0.617  0.250  0.959  1.0
  O  O17  1  0.383  0.750  0.041  1.0
  O  O18  1  0.935  0.168  0.636  1.0
  O  O19  1  0.065  0.832  0.364  1.0
  O  O20  1  0.407  0.122  0.325  1.0
  O  O21  1  0.593  0.878  0.675  1.0
[/CIF]
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