The material structure described by V9PO25 crystallizes in the tetragonal I-4 space group. There are three inequivalent V sites. In the first V site, V(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing VO6 octahedra. The corner-sharing octahedra are not tilted. In the second V site, V(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms. In the third V site, V(3) is bonded to one O(3), one O(4), one O(5), one O(7), and two equivalent O(6) atoms to form distorted VO6 octahedra that share corners with two equivalent V(3)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 32°. P(1) is bonded to four equivalent O(7) atoms to form PO4 tetrahedra that share corners with four equivalent V(3)O6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent V(1) atoms. In the second O site, O(2) is bonded in a linear geometry to one V(1) and one V(2) atom. In the third O site, O(3) is bonded in a linear geometry to one V(2) and one V(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one V(3) and two equivalent V(2) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to one V(2) and one V(3) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one V(2) and two equivalent V(3) atoms. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one V(3) and one P(1) atom. is represented by the CIF file [CIF]
data_V9PO25
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.863
_cell_length_b   10.863
_cell_length_c   10.863
_cell_angle_alpha   91.601
_cell_angle_beta   91.601
_cell_angle_gamma   160.754
_symmetry_Int_Tables_number   1
_cell_volume   416.594
_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
  V  V0  1  0.000  0.000  0.000  1.0
  V  V1  1  0.115  0.788  0.899  1.0
  V  V2  1  0.899  0.680  0.552  1.0
  V  V3  1  0.653  0.101  0.782  1.0
  V  V4  1  0.212  0.111  0.327  1.0
  V  V5  1  0.785  0.885  0.673  1.0
  V  V6  1  0.320  0.871  0.218  1.0
  V  V7  1  0.129  0.347  0.448  1.0
  V  V8  1  0.889  0.215  0.101  1.0
  P  P9  1  0.750  0.250  0.500  1.0
  O  O10  1  0.500  0.500  0.000  1.0
  O  O11  1  0.055  0.886  0.940  1.0
  O  O12  1  0.812  0.772  0.603  1.0
  O  O13  1  0.614  0.258  0.858  1.0
  O  O14  1  0.988  0.726  0.699  1.0
  O  O15  1  0.791  0.188  0.960  1.0
  O  O16  1  0.163  0.654  0.803  1.0
  O  O17  1  0.346  0.149  0.509  1.0
  O  O18  1  0.742  0.600  0.356  1.0
  O  O19  1  0.570  0.092  0.620  1.0
  O  O20  1  0.114  0.054  0.169  1.0
  O  O21  1  0.908  0.528  0.478  1.0
  O  O22  1  0.711  0.012  0.738  1.0
  O  O23  1  0.274  0.973  0.262  1.0
  O  O24  1  0.050  0.430  0.522  1.0
  O  O25  1  0.885  0.945  0.831  1.0
  O  O26  1  0.472  0.950  0.380  1.0
  O  O27  1  0.244  0.386  0.644  1.0
  O  O28  1  0.641  0.837  0.491  1.0
  O  O29  1  0.851  0.359  0.197  1.0
  O  O30  1  0.228  0.831  0.040  1.0
  O  O31  1  0.027  0.289  0.301  1.0
  O  O32  1  0.400  0.756  0.142  1.0
  O  O33  1  0.169  0.209  0.397  1.0
  O  O34  1  0.946  0.115  0.060  1.0
[/CIF]
.
The material structure described by V9PO25 crystallizes in the tetragonal I-4 space group. There are three inequivalent V sites. In the first V site, V(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing VO6 octahedra. The corner-sharing octahedra are not tilted. In the second V site, V(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms. In the third V site, V(3) is bonded to one O(3), one O(4), one O(5), one O(7), and two equivalent O(6) atoms to form distorted VO6 octahedra that share corners with two equivalent V(3)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 32°. P(1) is bonded to four equivalent O(7) atoms to form PO4 tetrahedra that share corners with four equivalent V(3)O6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent V(1) atoms. In the second O site, O(2) is bonded in a linear geometry to one V(1) and one V(2) atom. In the third O site, O(3) is bonded in a linear geometry to one V(2) and one V(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one V(3) and two equivalent V(2) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to one V(2) and one V(3) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one V(2) and two equivalent V(3) atoms. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one V(3) and one P(1) atom. is represented by the CIF file [CIF]
data_V9PO25
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.863
_cell_length_b   10.863
_cell_length_c   10.863
_cell_angle_alpha   91.601
_cell_angle_beta   91.601
_cell_angle_gamma   160.754
_symmetry_Int_Tables_number   1
_cell_volume   416.594
_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
  V  V0  1  0.000  0.000  0.000  1.0
  V  V1  1  0.115  0.788  0.899  1.0
  V  V2  1  0.899  0.680  0.552  1.0
  V  V3  1  0.653  0.101  0.782  1.0
  V  V4  1  0.212  0.111  0.327  1.0
  V  V5  1  0.785  0.885  0.673  1.0
  V  V6  1  0.320  0.871  0.218  1.0
  V  V7  1  0.129  0.347  0.448  1.0
  V  V8  1  0.889  0.215  0.101  1.0
  P  P9  1  0.750  0.250  0.500  1.0
  O  O10  1  0.500  0.500  0.000  1.0
  O  O11  1  0.055  0.886  0.940  1.0
  O  O12  1  0.812  0.772  0.603  1.0
  O  O13  1  0.614  0.258  0.858  1.0
  O  O14  1  0.988  0.726  0.699  1.0
  O  O15  1  0.791  0.188  0.960  1.0
  O  O16  1  0.163  0.654  0.803  1.0
  O  O17  1  0.346  0.149  0.509  1.0
  O  O18  1  0.742  0.600  0.356  1.0
  O  O19  1  0.570  0.092  0.620  1.0
  O  O20  1  0.114  0.054  0.169  1.0
  O  O21  1  0.908  0.528  0.478  1.0
  O  O22  1  0.711  0.012  0.738  1.0
  O  O23  1  0.274  0.973  0.262  1.0
  O  O24  1  0.050  0.430  0.522  1.0
  O  O25  1  0.885  0.945  0.831  1.0
  O  O26  1  0.472  0.950  0.380  1.0
  O  O27  1  0.244  0.386  0.644  1.0
  O  O28  1  0.641  0.837  0.491  1.0
  O  O29  1  0.851  0.359  0.197  1.0
  O  O30  1  0.228  0.831  0.040  1.0
  O  O31  1  0.027  0.289  0.301  1.0
  O  O32  1  0.400  0.756  0.142  1.0
  O  O33  1  0.169  0.209  0.397  1.0
  O  O34  1  0.946  0.115  0.060  1.0
[/CIF]
.