The structure described by CaVSi4(H2O5)3 crystallizes in the orthorhombic Cmc2_1 space group. Ca(1) is bonded in a 7-coordinate geometry to one O(9), two equivalent O(1), two equivalent O(2), and two equivalent O(7) atoms. V(1) is bonded to one O(6), two equivalent O(1), and two equivalent O(2) atoms to form distorted VO5 trigonal bipyramids that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with three equivalent Si(2)O4 tetrahedra and  a cornercorner with one V(1)O5 trigonal bipyramid. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with three equivalent Si(1)O4 tetrahedra and  a cornercorner with one V(1)O5 trigonal bipyramid. There are four inequivalent H sites. In the first H site, H(3) is bonded in a linear geometry to one O(8) and one O(9) atom. In the second H site, H(4) is bonded in a single-bond geometry to one O(8) atom. In the third H site, H(1) is bonded in a linear geometry to one O(7) and one O(8) atom. In the fourth H site, H(2) is bonded in a single-bond geometry to one O(7) atom. There are nine inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(6) is bonded in a single-bond geometry to one V(1) atom. In the third O site, O(7) is bonded in a distorted water-like geometry to one Ca(1), one H(1), and one H(2) atom. In the fourth O site, O(8) is bonded in a distorted tetrahedral geometry to one H(3), one H(4), and two equivalent H(1) atoms. In the fifth O site, O(9) is bonded in a linear geometry to one Ca(1) and one H(3) atom. In the sixth O site, O(4) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(2) atom. In the seventh O site, O(1) is bonded in a 3-coordinate geometry to one Ca(1), one V(1), and one Si(1) atom. In the eighth O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one V(1), and one Si(2) atom. In the ninth O site, O(3) is bonded in a linear geometry to one Si(1) and one Si(2) atom. is represented by the CIF file [CIF]
data_CaVSi4(H2O5)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.848
_cell_length_b   8.848
_cell_length_c   9.004
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   107.790
_symmetry_Int_Tables_number   1
_cell_volume   671.109
_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
  Ca  Ca0  1  0.247  0.247  0.740  1.0
  Ca  Ca1  1  0.753  0.753  0.240  1.0
  V  V2  1  0.954  0.954  0.573  1.0
  V  V3  1  0.046  0.046  0.073  1.0
  Si  Si4  1  0.305  0.896  0.609  1.0
  Si  Si5  1  0.896  0.305  0.609  1.0
  Si  Si6  1  0.695  0.104  0.109  1.0
  Si  Si7  1  0.104  0.695  0.109  1.0
  Si  Si8  1  0.357  0.947  0.953  1.0
  Si  Si9  1  0.947  0.357  0.953  1.0
  Si  Si10  1  0.643  0.053  0.453  1.0
  Si  Si11  1  0.053  0.643  0.453  1.0
  H  H12  1  0.562  0.415  0.759  1.0
  H  H13  1  0.415  0.562  0.759  1.0
  H  H14  1  0.438  0.585  0.259  1.0
  H  H15  1  0.585  0.438  0.259  1.0
  H  H16  1  0.578  0.250  0.703  1.0
  H  H17  1  0.250  0.578  0.703  1.0
  H  H18  1  0.422  0.750  0.203  1.0
  H  H19  1  0.750  0.422  0.203  1.0
  H  H20  1  0.644  0.644  0.883  1.0
  H  H21  1  0.356  0.356  0.383  1.0
  H  H22  1  0.658  0.658  0.674  1.0
  H  H23  1  0.342  0.342  0.174  1.0
  O  O24  1  0.178  0.996  0.596  1.0
  O  O25  1  0.996  0.178  0.596  1.0
  O  O26  1  0.822  0.004  0.096  1.0
  O  O27  1  0.004  0.822  0.096  1.0
  O  O28  1  0.236  0.055  0.963  1.0
  O  O29  1  0.055  0.236  0.963  1.0
  O  O30  1  0.764  0.945  0.463  1.0
  O  O31  1  0.945  0.764  0.463  1.0
  O  O32  1  0.462  0.968  0.507  1.0
  O  O33  1  0.968  0.462  0.507  1.0
  O  O34  1  0.538  0.032  0.007  1.0
  O  O35  1  0.032  0.538  0.007  1.0
  O  O36  1  0.211  0.713  0.558  1.0
  O  O37  1  0.713  0.211  0.558  1.0
  O  O38  1  0.789  0.287  0.058  1.0
  O  O39  1  0.287  0.789  0.058  1.0
  O  O40  1  0.365  0.895  0.780  1.0
  O  O41  1  0.895  0.365  0.780  1.0
  O  O42  1  0.635  0.105  0.280  1.0
  O  O43  1  0.105  0.635  0.280  1.0
  O  O44  1  0.891  0.891  0.736  1.0
  O  O45  1  0.109  0.109  0.236  1.0
  O  O46  1  0.516  0.293  0.772  1.0
  O  O47  1  0.293  0.516  0.772  1.0
  O  O48  1  0.484  0.707  0.272  1.0
  O  O49  1  0.707  0.484  0.272  1.0
  O  O50  1  0.595  0.595  0.753  1.0
  O  O51  1  0.405  0.405  0.253  1.0
  O  O52  1  0.330  0.330  0.506  1.0
  O  O53  1  0.670  0.670  0.006  1.0
[/CIF]
.
The structure described by CaVSi4(H2O5)3 crystallizes in the orthorhombic Cmc2_1 space group. Ca(1) is bonded in a 7-coordinate geometry to one O(9), two equivalent O(1), two equivalent O(2), and two equivalent O(7) atoms. V(1) is bonded to one O(6), two equivalent O(1), and two equivalent O(2) atoms to form distorted VO5 trigonal bipyramids that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with three equivalent Si(2)O4 tetrahedra and  a cornercorner with one V(1)O5 trigonal bipyramid. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with three equivalent Si(1)O4 tetrahedra and  a cornercorner with one V(1)O5 trigonal bipyramid. There are four inequivalent H sites. In the first H site, H(3) is bonded in a linear geometry to one O(8) and one O(9) atom. In the second H site, H(4) is bonded in a single-bond geometry to one O(8) atom. In the third H site, H(1) is bonded in a linear geometry to one O(7) and one O(8) atom. In the fourth H site, H(2) is bonded in a single-bond geometry to one O(7) atom. There are nine inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(6) is bonded in a single-bond geometry to one V(1) atom. In the third O site, O(7) is bonded in a distorted water-like geometry to one Ca(1), one H(1), and one H(2) atom. In the fourth O site, O(8) is bonded in a distorted tetrahedral geometry to one H(3), one H(4), and two equivalent H(1) atoms. In the fifth O site, O(9) is bonded in a linear geometry to one Ca(1) and one H(3) atom. In the sixth O site, O(4) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(2) atom. In the seventh O site, O(1) is bonded in a 3-coordinate geometry to one Ca(1), one V(1), and one Si(1) atom. In the eighth O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one V(1), and one Si(2) atom. In the ninth O site, O(3) is bonded in a linear geometry to one Si(1) and one Si(2) atom. is represented by the CIF file [CIF]
data_CaVSi4(H2O5)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.848
_cell_length_b   8.848
_cell_length_c   9.004
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   107.790
_symmetry_Int_Tables_number   1
_cell_volume   671.109
_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
  Ca  Ca0  1  0.247  0.247  0.740  1.0
  Ca  Ca1  1  0.753  0.753  0.240  1.0
  V  V2  1  0.954  0.954  0.573  1.0
  V  V3  1  0.046  0.046  0.073  1.0
  Si  Si4  1  0.305  0.896  0.609  1.0
  Si  Si5  1  0.896  0.305  0.609  1.0
  Si  Si6  1  0.695  0.104  0.109  1.0
  Si  Si7  1  0.104  0.695  0.109  1.0
  Si  Si8  1  0.357  0.947  0.953  1.0
  Si  Si9  1  0.947  0.357  0.953  1.0
  Si  Si10  1  0.643  0.053  0.453  1.0
  Si  Si11  1  0.053  0.643  0.453  1.0
  H  H12  1  0.562  0.415  0.759  1.0
  H  H13  1  0.415  0.562  0.759  1.0
  H  H14  1  0.438  0.585  0.259  1.0
  H  H15  1  0.585  0.438  0.259  1.0
  H  H16  1  0.578  0.250  0.703  1.0
  H  H17  1  0.250  0.578  0.703  1.0
  H  H18  1  0.422  0.750  0.203  1.0
  H  H19  1  0.750  0.422  0.203  1.0
  H  H20  1  0.644  0.644  0.883  1.0
  H  H21  1  0.356  0.356  0.383  1.0
  H  H22  1  0.658  0.658  0.674  1.0
  H  H23  1  0.342  0.342  0.174  1.0
  O  O24  1  0.178  0.996  0.596  1.0
  O  O25  1  0.996  0.178  0.596  1.0
  O  O26  1  0.822  0.004  0.096  1.0
  O  O27  1  0.004  0.822  0.096  1.0
  O  O28  1  0.236  0.055  0.963  1.0
  O  O29  1  0.055  0.236  0.963  1.0
  O  O30  1  0.764  0.945  0.463  1.0
  O  O31  1  0.945  0.764  0.463  1.0
  O  O32  1  0.462  0.968  0.507  1.0
  O  O33  1  0.968  0.462  0.507  1.0
  O  O34  1  0.538  0.032  0.007  1.0
  O  O35  1  0.032  0.538  0.007  1.0
  O  O36  1  0.211  0.713  0.558  1.0
  O  O37  1  0.713  0.211  0.558  1.0
  O  O38  1  0.789  0.287  0.058  1.0
  O  O39  1  0.287  0.789  0.058  1.0
  O  O40  1  0.365  0.895  0.780  1.0
  O  O41  1  0.895  0.365  0.780  1.0
  O  O42  1  0.635  0.105  0.280  1.0
  O  O43  1  0.105  0.635  0.280  1.0
  O  O44  1  0.891  0.891  0.736  1.0
  O  O45  1  0.109  0.109  0.236  1.0
  O  O46  1  0.516  0.293  0.772  1.0
  O  O47  1  0.293  0.516  0.772  1.0
  O  O48  1  0.484  0.707  0.272  1.0
  O  O49  1  0.707  0.484  0.272  1.0
  O  O50  1  0.595  0.595  0.753  1.0
  O  O51  1  0.405  0.405  0.253  1.0
  O  O52  1  0.330  0.330  0.506  1.0
  O  O53  1  0.670  0.670  0.006  1.0
[/CIF]
.