The compound described by Ba2VO(PO4)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(5), one O(9), two equivalent O(10), two equivalent O(6), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(3), one O(6), two equivalent O(5), two equivalent O(7), and two equivalent O(9) atoms. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(7) atoms to form VO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. In the second V site, V(2) is bonded to one O(2), two equivalent O(4), and two equivalent O(8) atoms to form VO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(4), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O5 trigonal bipyramid and  a cornercorner with one V(2)O5 trigonal bipyramid. In the second P site, P(2) is bonded to one O(10), one O(3), one O(6), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O5 trigonal bipyramid and  a cornercorner with one V(2)O5 trigonal bipyramid. There are ten inequivalent O sites. In the first O site, O(8) is bonded in a 2-coordinate geometry to two equivalent Ba(1), one V(2), and one P(2) atom. In the second O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one P(1) atom. In the third O site, O(10) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one P(2) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one V(1) atom. In the fifth O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one V(2) atom. In the sixth O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Ba(2), one V(1), and one P(2) atom. In the seventh O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one V(2), and one P(1) atom. In the eighth O site, O(5) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one P(1) atom. In the ninth O site, O(6) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one P(2) atom. In the tenth O site, O(7) is bonded in a 2-coordinate geometry to two equivalent Ba(2), one V(1), and one P(1) atom. is represented by the CIF file [CIF]
data_Ba2VP2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.559
_cell_length_b   9.354
_cell_length_c   9.600
_cell_angle_alpha   108.876
_cell_angle_beta   90.000
_cell_angle_gamma   107.288
_symmetry_Int_Tables_number   1
_cell_volume   448.471
_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
  Ba  Ba0  1  0.709  0.327  0.578  1.0
  Ba  Ba1  1  0.348  0.674  0.922  1.0
  Ba  Ba2  1  0.674  0.326  0.078  1.0
  Ba  Ba3  1  0.382  0.673  0.422  1.0
  O  O4  1  0.664  0.000  0.000  1.0
  O  O5  1  0.393  0.000  0.500  1.0
  O  O6  1  0.070  0.886  0.815  1.0
  O  O7  1  0.876  0.886  0.314  1.0
  O  O8  1  0.990  0.114  0.686  1.0
  O  O9  1  0.183  0.114  0.185  1.0
  O  O10  1  0.977  0.380  0.851  1.0
  O  O11  1  0.458  0.380  0.352  1.0
  O  O12  1  0.078  0.620  0.648  1.0
  O  O13  1  0.597  0.620  0.149  1.0
  O  O14  1  0.915  0.794  0.037  1.0
  O  O15  1  0.121  0.206  0.963  1.0
  O  O16  1  0.138  0.205  0.462  1.0
  O  O17  1  0.933  0.795  0.538  1.0
  O  O18  1  0.068  0.659  0.191  1.0
  O  O19  1  0.649  0.662  0.693  1.0
  O  O20  1  0.987  0.338  0.307  1.0
  O  O21  1  0.408  0.341  0.809  1.0
  P  P22  1  0.130  0.262  0.824  1.0
  P  P23  1  0.927  0.739  0.677  1.0
  P  P24  1  0.868  0.738  0.176  1.0
  P  P25  1  0.187  0.261  0.323  1.0
  V  V26  1  0.965  0.000  0.000  1.0
  V  V27  1  0.092  0.000  0.500  1.0
[/CIF]
.
The compound described by Ba2VO(PO4)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(5), one O(9), two equivalent O(10), two equivalent O(6), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(3), one O(6), two equivalent O(5), two equivalent O(7), and two equivalent O(9) atoms. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(7) atoms to form VO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. In the second V site, V(2) is bonded to one O(2), two equivalent O(4), and two equivalent O(8) atoms to form VO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(4), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O5 trigonal bipyramid and  a cornercorner with one V(2)O5 trigonal bipyramid. In the second P site, P(2) is bonded to one O(10), one O(3), one O(6), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one V(1)O5 trigonal bipyramid and  a cornercorner with one V(2)O5 trigonal bipyramid. There are ten inequivalent O sites. In the first O site, O(8) is bonded in a 2-coordinate geometry to two equivalent Ba(1), one V(2), and one P(2) atom. In the second O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one P(1) atom. In the third O site, O(10) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one P(2) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one V(1) atom. In the fifth O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one V(2) atom. In the sixth O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Ba(2), one V(1), and one P(2) atom. In the seventh O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one V(2), and one P(1) atom. In the eighth O site, O(5) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one P(1) atom. In the ninth O site, O(6) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one P(2) atom. In the tenth O site, O(7) is bonded in a 2-coordinate geometry to two equivalent Ba(2), one V(1), and one P(1) atom. is represented by the CIF file [CIF]
data_Ba2VP2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.559
_cell_length_b   9.354
_cell_length_c   9.600
_cell_angle_alpha   108.876
_cell_angle_beta   90.000
_cell_angle_gamma   107.288
_symmetry_Int_Tables_number   1
_cell_volume   448.471
_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
  Ba  Ba0  1  0.709  0.327  0.578  1.0
  Ba  Ba1  1  0.348  0.674  0.922  1.0
  Ba  Ba2  1  0.674  0.326  0.078  1.0
  Ba  Ba3  1  0.382  0.673  0.422  1.0
  O  O4  1  0.664  0.000  0.000  1.0
  O  O5  1  0.393  0.000  0.500  1.0
  O  O6  1  0.070  0.886  0.815  1.0
  O  O7  1  0.876  0.886  0.314  1.0
  O  O8  1  0.990  0.114  0.686  1.0
  O  O9  1  0.183  0.114  0.185  1.0
  O  O10  1  0.977  0.380  0.851  1.0
  O  O11  1  0.458  0.380  0.352  1.0
  O  O12  1  0.078  0.620  0.648  1.0
  O  O13  1  0.597  0.620  0.149  1.0
  O  O14  1  0.915  0.794  0.037  1.0
  O  O15  1  0.121  0.206  0.963  1.0
  O  O16  1  0.138  0.205  0.462  1.0
  O  O17  1  0.933  0.795  0.538  1.0
  O  O18  1  0.068  0.659  0.191  1.0
  O  O19  1  0.649  0.662  0.693  1.0
  O  O20  1  0.987  0.338  0.307  1.0
  O  O21  1  0.408  0.341  0.809  1.0
  P  P22  1  0.130  0.262  0.824  1.0
  P  P23  1  0.927  0.739  0.677  1.0
  P  P24  1  0.868  0.738  0.176  1.0
  P  P25  1  0.187  0.261  0.323  1.0
  V  V26  1  0.965  0.000  0.000  1.0
  V  V27  1  0.092  0.000  0.500  1.0
[/CIF]
.