The crystal structure described by Ba2P2O7 crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 11-coordinate geometry to one O(7), two equivalent O(5), four equivalent O(2), and four equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(6), two equivalent O(1), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to four equivalent O(3) and four equivalent O(4) atoms. 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(6) atom to form corner-sharing PO4 tetrahedra. In the second P site, P(2) is bonded to one O(5), one O(7), and two equivalent O(4) atoms to form corner-sharing PO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(3), one Ba(4), and one P(2) atom. In the second O site, O(5) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(3), and one P(2) atom. In the third O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Ba(3) and two equivalent P(1) atoms. In the fourth O site, O(7) is bonded in a bent 150 degrees geometry to one Ba(2) and two equivalent P(2) atoms. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to one Ba(3), two equivalent Ba(1), and one P(1) atom. In the sixth O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one P(1) atom. In the seventh O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(4), and one P(1) atom. is represented by the CIF card [CIF]
data_Ba2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.487
_cell_length_b   9.487
_cell_length_c   7.275
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.088
_symmetry_Int_Tables_number   1
_cell_volume   566.498
_cell_formula_units_Z   3
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  0.004  0.617  0.500  1.0
  Ba  Ba1  1  0.386  0.386  0.500  1.0
  Ba  Ba2  1  0.617  0.004  0.500  1.0
  Ba  Ba3  1  0.287  0.995  0.000  1.0
  Ba  Ba4  1  0.995  0.287  0.000  1.0
  Ba  Ba5  1  0.714  0.714  0.000  1.0
  P  P6  1  0.338  0.675  0.222  1.0
  P  P7  1  0.338  0.675  0.778  1.0
  P  P8  1  0.675  0.338  0.222  1.0
  P  P9  1  0.675  0.338  0.778  1.0
  P  P10  1  0.008  0.008  0.283  1.0
  P  P11  1  0.008  0.008  0.717  1.0
  O  O12  1  0.323  0.818  0.297  1.0
  O  O13  1  0.185  0.510  0.258  1.0
  O  O14  1  0.495  0.679  0.278  1.0
  O  O15  1  0.323  0.818  0.703  1.0
  O  O16  1  0.185  0.510  0.742  1.0
  O  O17  1  0.495  0.679  0.722  1.0
  O  O18  1  0.510  0.185  0.258  1.0
  O  O19  1  0.679  0.495  0.278  1.0
  O  O20  1  0.818  0.323  0.297  1.0
  O  O21  1  0.510  0.185  0.742  1.0
  O  O22  1  0.679  0.495  0.722  1.0
  O  O23  1  0.818  0.323  0.703  1.0
  O  O24  1  0.847  0.002  0.237  1.0
  O  O25  1  0.002  0.847  0.237  1.0
  O  O26  1  0.158  0.158  0.201  1.0
  O  O27  1  0.847  0.002  0.763  1.0
  O  O28  1  0.002  0.847  0.763  1.0
  O  O29  1  0.158  0.158  0.799  1.0
  O  O30  1  0.711  0.355  0.000  1.0
  O  O31  1  0.355  0.711  0.000  1.0
  O  O32  1  0.044  0.044  0.500  1.0
[/CIF]
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The crystal structure described by Ba2P2O7 crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 11-coordinate geometry to one O(7), two equivalent O(5), four equivalent O(2), and four equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(6), two equivalent O(1), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to four equivalent O(3) and four equivalent O(4) atoms. 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(6) atom to form corner-sharing PO4 tetrahedra. In the second P site, P(2) is bonded to one O(5), one O(7), and two equivalent O(4) atoms to form corner-sharing PO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(3), one Ba(4), and one P(2) atom. In the second O site, O(5) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(3), and one P(2) atom. In the third O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Ba(3) and two equivalent P(1) atoms. In the fourth O site, O(7) is bonded in a bent 150 degrees geometry to one Ba(2) and two equivalent P(2) atoms. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to one Ba(3), two equivalent Ba(1), and one P(1) atom. In the sixth O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one P(1) atom. In the seventh O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(4), and one P(1) atom. is represented by the CIF card [CIF]
data_Ba2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.487
_cell_length_b   9.487
_cell_length_c   7.275
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.088
_symmetry_Int_Tables_number   1
_cell_volume   566.498
_cell_formula_units_Z   3
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  0.004  0.617  0.500  1.0
  Ba  Ba1  1  0.386  0.386  0.500  1.0
  Ba  Ba2  1  0.617  0.004  0.500  1.0
  Ba  Ba3  1  0.287  0.995  0.000  1.0
  Ba  Ba4  1  0.995  0.287  0.000  1.0
  Ba  Ba5  1  0.714  0.714  0.000  1.0
  P  P6  1  0.338  0.675  0.222  1.0
  P  P7  1  0.338  0.675  0.778  1.0
  P  P8  1  0.675  0.338  0.222  1.0
  P  P9  1  0.675  0.338  0.778  1.0
  P  P10  1  0.008  0.008  0.283  1.0
  P  P11  1  0.008  0.008  0.717  1.0
  O  O12  1  0.323  0.818  0.297  1.0
  O  O13  1  0.185  0.510  0.258  1.0
  O  O14  1  0.495  0.679  0.278  1.0
  O  O15  1  0.323  0.818  0.703  1.0
  O  O16  1  0.185  0.510  0.742  1.0
  O  O17  1  0.495  0.679  0.722  1.0
  O  O18  1  0.510  0.185  0.258  1.0
  O  O19  1  0.679  0.495  0.278  1.0
  O  O20  1  0.818  0.323  0.297  1.0
  O  O21  1  0.510  0.185  0.742  1.0
  O  O22  1  0.679  0.495  0.722  1.0
  O  O23  1  0.818  0.323  0.703  1.0
  O  O24  1  0.847  0.002  0.237  1.0
  O  O25  1  0.002  0.847  0.237  1.0
  O  O26  1  0.158  0.158  0.201  1.0
  O  O27  1  0.847  0.002  0.763  1.0
  O  O28  1  0.002  0.847  0.763  1.0
  O  O29  1  0.158  0.158  0.799  1.0
  O  O30  1  0.711  0.355  0.000  1.0
  O  O31  1  0.355  0.711  0.000  1.0
  O  O32  1  0.044  0.044  0.500  1.0
[/CIF]
.