The structure described by (Nb(SiO3)4)2O2 crystallizes in the monoclinic P2_1/m space group. The structure consists of two water atoms inside a Nb(SiO3)4 framework. In the Nb(SiO3)4 framework, Nb(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with four equivalent Si(3)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(5), one O(6), and two equivalent O(7) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(6), and two equivalent O(8) atoms to form SiO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. In the third Si site, Si(3) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and  a cornercorner with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 24-30°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Nb(1) and one Si(3) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Nb(1) and one Si(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Nb(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Nb(1) and one Si(3) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. is represented by the CIF card [CIF]
data_NbSi4O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.103
_cell_length_b   7.598
_cell_length_c   9.999
_cell_angle_alpha   72.019
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   657.824
_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
  Nb  Nb0  1  0.750  0.085  0.103  1.0
  Nb  Nb1  1  0.250  0.915  0.897  1.0
  Si  Si2  1  0.750  0.412  0.584  1.0
  Si  Si3  1  0.250  0.588  0.416  1.0
  Si  Si4  1  0.750  0.440  0.258  1.0
  Si  Si5  1  0.250  0.560  0.742  1.0
  Si  Si6  1  0.997  0.268  0.811  1.0
  Si  Si7  1  0.497  0.732  0.189  1.0
  Si  Si8  1  0.003  0.732  0.189  1.0
  Si  Si9  1  0.503  0.268  0.811  1.0
  O  O10  1  0.400  0.776  0.045  1.0
  O  O11  1  0.900  0.224  0.955  1.0
  O  O12  1  0.600  0.224  0.955  1.0
  O  O13  1  0.100  0.776  0.045  1.0
  O  O14  1  0.750  0.251  0.214  1.0
  O  O15  1  0.250  0.749  0.786  1.0
  O  O16  1  0.750  0.994  0.925  1.0
  O  O17  1  0.250  0.006  0.075  1.0
  O  O18  1  0.098  0.089  0.812  1.0
  O  O19  1  0.598  0.911  0.188  1.0
  O  O20  1  0.902  0.911  0.188  1.0
  O  O21  1  0.402  0.089  0.812  1.0
  O  O22  1  0.750  0.641  0.545  1.0
  O  O23  1  0.250  0.359  0.455  1.0
  O  O24  1  0.750  0.382  0.430  1.0
  O  O25  1  0.250  0.618  0.570  1.0
  O  O26  1  0.605  0.318  0.671  1.0
  O  O27  1  0.105  0.682  0.329  1.0
  O  O28  1  0.395  0.682  0.329  1.0
  O  O29  1  0.895  0.318  0.671  1.0
  O  O30  1  0.398  0.444  0.805  1.0
  O  O31  1  0.898  0.556  0.195  1.0
  O  O32  1  0.602  0.556  0.195  1.0
  O  O33  1  0.102  0.444  0.805  1.0
  O  O34  1  0.500  0.000  0.500  1.0
  O  O35  1  0.000  0.000  0.500  1.0
[/CIF]
.
The structure described by (Nb(SiO3)4)2O2 crystallizes in the monoclinic P2_1/m space group. The structure consists of two water atoms inside a Nb(SiO3)4 framework. In the Nb(SiO3)4 framework, Nb(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with four equivalent Si(3)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(5), one O(6), and two equivalent O(7) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(6), and two equivalent O(8) atoms to form SiO4 tetrahedra that share  a cornercorner with one Nb(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. In the third Si site, Si(3) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and  a cornercorner with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 24-30°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Nb(1) and one Si(3) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Nb(1) and one Si(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Nb(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Nb(1) and one Si(3) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. is represented by the CIF card [CIF]
data_NbSi4O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.103
_cell_length_b   7.598
_cell_length_c   9.999
_cell_angle_alpha   72.019
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   657.824
_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
  Nb  Nb0  1  0.750  0.085  0.103  1.0
  Nb  Nb1  1  0.250  0.915  0.897  1.0
  Si  Si2  1  0.750  0.412  0.584  1.0
  Si  Si3  1  0.250  0.588  0.416  1.0
  Si  Si4  1  0.750  0.440  0.258  1.0
  Si  Si5  1  0.250  0.560  0.742  1.0
  Si  Si6  1  0.997  0.268  0.811  1.0
  Si  Si7  1  0.497  0.732  0.189  1.0
  Si  Si8  1  0.003  0.732  0.189  1.0
  Si  Si9  1  0.503  0.268  0.811  1.0
  O  O10  1  0.400  0.776  0.045  1.0
  O  O11  1  0.900  0.224  0.955  1.0
  O  O12  1  0.600  0.224  0.955  1.0
  O  O13  1  0.100  0.776  0.045  1.0
  O  O14  1  0.750  0.251  0.214  1.0
  O  O15  1  0.250  0.749  0.786  1.0
  O  O16  1  0.750  0.994  0.925  1.0
  O  O17  1  0.250  0.006  0.075  1.0
  O  O18  1  0.098  0.089  0.812  1.0
  O  O19  1  0.598  0.911  0.188  1.0
  O  O20  1  0.902  0.911  0.188  1.0
  O  O21  1  0.402  0.089  0.812  1.0
  O  O22  1  0.750  0.641  0.545  1.0
  O  O23  1  0.250  0.359  0.455  1.0
  O  O24  1  0.750  0.382  0.430  1.0
  O  O25  1  0.250  0.618  0.570  1.0
  O  O26  1  0.605  0.318  0.671  1.0
  O  O27  1  0.105  0.682  0.329  1.0
  O  O28  1  0.395  0.682  0.329  1.0
  O  O29  1  0.895  0.318  0.671  1.0
  O  O30  1  0.398  0.444  0.805  1.0
  O  O31  1  0.898  0.556  0.195  1.0
  O  O32  1  0.602  0.556  0.195  1.0
  O  O33  1  0.102  0.444  0.805  1.0
  O  O34  1  0.500  0.000  0.500  1.0
  O  O35  1  0.000  0.000  0.500  1.0
[/CIF]
.