The crystal structure described by Ba2CaV2(Si2O7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(12), one O(13), one O(2), one O(3), one O(4), one O(7), and one O(9) atom. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(13), one O(14), one O(2), one O(4), and one O(8) atom. Ca(1) is bonded in a 5-coordinate geometry to one O(14), one O(3), one O(4), one O(7), and one O(8) atom. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(12), one O(14), one O(2), one O(7), and one O(8) atom to form VO5 trigonal bipyramids that share  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one V(2)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(1), one O(11), one O(3), one O(7), and one O(8) atom to form VO5 trigonal bipyramids that share  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one V(1)O5 trigonal bipyramid. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(11), one O(5), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent V(2)O5 trigonal bipyramids. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(2), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent V(1)O5 trigonal bipyramids. In the third Si site, Si(3) is bonded to one O(13), one O(3), one O(6), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and  a cornercorner with one V(2)O5 trigonal bipyramid. In the fourth Si site, Si(4) is bonded to one O(10), one O(14), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one V(1)O5 trigonal bipyramid. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one V(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one V(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ba(1), one Ca(1), one V(2), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Ca(1), and one Si(4) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Si(1) and one Si(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ba(1), one Ca(1), one V(1), and one V(2) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Ba(2), one Ca(1), one V(1), and one V(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Si(1), and one Si(3) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Si(2), and one Si(4) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one V(2), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one V(1), and one Si(2) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Ba(1), one Ba(2), and one Si(3) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Ba(2), one Ca(1), one V(1), and one Si(4) atom. is represented by the CIF card [CIF]
data_Ba2CaV2(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.940
_cell_length_b   7.299
_cell_length_c   8.651
_cell_angle_alpha   98.396
_cell_angle_beta   114.577
_cell_angle_gamma   77.543
_symmetry_Int_Tables_number   1
_cell_volume   332.372
_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  0.786  0.754  0.576  1.0
  Ba  Ba1  1  0.288  0.244  0.429  1.0
  Ca  Ca2  1  0.108  0.966  0.033  1.0
  V  V3  1  0.061  0.602  0.166  1.0
  V  V4  1  0.993  0.367  0.845  1.0
  Si  Si5  1  0.426  0.519  0.809  1.0
  Si  Si6  1  0.639  0.460  0.216  1.0
  Si  Si7  1  0.351  0.970  0.785  1.0
  Si  Si8  1  0.692  0.018  0.189  1.0
  O  O9  1  0.175  0.420  0.711  1.0
  O  O10  1  0.431  0.555  0.296  1.0
  O  O11  1  0.068  0.073  0.771  1.0
  O  O12  1  0.512  0.958  0.264  1.0
  O  O13  1  0.542  0.489  0.013  1.0
  O  O14  1  0.553  0.023  0.979  1.0
  O  O15  1  0.984  0.656  0.943  1.0
  O  O16  1  0.088  0.314  0.073  1.0
  O  O17  1  0.326  0.745  0.781  1.0
  O  O18  1  0.735  0.238  0.262  1.0
  O  O19  1  0.624  0.430  0.720  1.0
  O  O20  1  0.892  0.555  0.313  1.0
  O  O21  1  0.450  0.994  0.646  1.0
  O  O22  1  0.976  0.900  0.234  1.0
[/CIF]
.
The crystal structure described by Ba2CaV2(Si2O7)2 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(12), one O(13), one O(2), one O(3), one O(4), one O(7), and one O(9) atom. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(13), one O(14), one O(2), one O(4), and one O(8) atom. Ca(1) is bonded in a 5-coordinate geometry to one O(14), one O(3), one O(4), one O(7), and one O(8) atom. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(12), one O(14), one O(2), one O(7), and one O(8) atom to form VO5 trigonal bipyramids that share  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one V(2)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(1), one O(11), one O(3), one O(7), and one O(8) atom to form VO5 trigonal bipyramids that share  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one V(1)O5 trigonal bipyramid. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(11), one O(5), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent V(2)O5 trigonal bipyramids. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(2), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent V(1)O5 trigonal bipyramids. In the third Si site, Si(3) is bonded to one O(13), one O(3), one O(6), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and  a cornercorner with one V(2)O5 trigonal bipyramid. In the fourth Si site, Si(4) is bonded to one O(10), one O(14), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one V(1)O5 trigonal bipyramid. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one V(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one V(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ba(1), one Ca(1), one V(2), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Ca(1), and one Si(4) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Si(1) and one Si(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ba(1), one Ca(1), one V(1), and one V(2) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Ba(2), one Ca(1), one V(1), and one V(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Si(1), and one Si(3) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Si(2), and one Si(4) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one V(2), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one V(1), and one Si(2) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Ba(1), one Ba(2), and one Si(3) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Ba(2), one Ca(1), one V(1), and one Si(4) atom. is represented by the CIF card [CIF]
data_Ba2CaV2(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.940
_cell_length_b   7.299
_cell_length_c   8.651
_cell_angle_alpha   98.396
_cell_angle_beta   114.577
_cell_angle_gamma   77.543
_symmetry_Int_Tables_number   1
_cell_volume   332.372
_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  0.786  0.754  0.576  1.0
  Ba  Ba1  1  0.288  0.244  0.429  1.0
  Ca  Ca2  1  0.108  0.966  0.033  1.0
  V  V3  1  0.061  0.602  0.166  1.0
  V  V4  1  0.993  0.367  0.845  1.0
  Si  Si5  1  0.426  0.519  0.809  1.0
  Si  Si6  1  0.639  0.460  0.216  1.0
  Si  Si7  1  0.351  0.970  0.785  1.0
  Si  Si8  1  0.692  0.018  0.189  1.0
  O  O9  1  0.175  0.420  0.711  1.0
  O  O10  1  0.431  0.555  0.296  1.0
  O  O11  1  0.068  0.073  0.771  1.0
  O  O12  1  0.512  0.958  0.264  1.0
  O  O13  1  0.542  0.489  0.013  1.0
  O  O14  1  0.553  0.023  0.979  1.0
  O  O15  1  0.984  0.656  0.943  1.0
  O  O16  1  0.088  0.314  0.073  1.0
  O  O17  1  0.326  0.745  0.781  1.0
  O  O18  1  0.735  0.238  0.262  1.0
  O  O19  1  0.624  0.430  0.720  1.0
  O  O20  1  0.892  0.555  0.313  1.0
  O  O21  1  0.450  0.994  0.646  1.0
  O  O22  1  0.976  0.900  0.234  1.0
[/CIF]
.