The compound described by Li2Nb4O11 crystallizes in the monoclinic C2/c space group. Li(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form distorted LiO4 trigonal pyramids that share corners with three equivalent Nb(2)O6 octahedra and  an edgeedge with one Nb(3)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 55-56°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms. In the second Nb site, Nb(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(3)O7 pentagonal bipyramids and corners with six equivalent Li(1)O4 trigonal pyramids. In the third Nb site, Nb(3) is bonded to one O(6), two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted NbO7 pentagonal bipyramids that share corners with two equivalent Nb(2)O6 octahedra and edges with two equivalent Li(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to one Nb(3) and two equivalent Nb(1) atoms. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(3) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fifth O site, O(4) is bonded to one Li(1), one Nb(3), and two equivalent Nb(1) atoms to form corner-sharing OLiNb3 tetrahedra. In the sixth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(2), and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Nb4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.354
_cell_length_b   6.354
_cell_length_c   12.930
_cell_angle_alpha   75.682
_cell_angle_beta   75.682
_cell_angle_gamma   59.249
_symmetry_Int_Tables_number   1
_cell_volume   430.029
_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
  Li  Li0  1  0.855  0.357  0.940  1.0
  Li  Li1  1  0.643  0.145  0.560  1.0
  Li  Li2  1  0.357  0.855  0.440  1.0
  Li  Li3  1  0.145  0.643  0.060  1.0
  Nb  Nb4  1  0.751  0.604  0.250  1.0
  Nb  Nb5  1  0.604  0.751  0.750  1.0
  Nb  Nb6  1  0.000  0.500  0.500  1.0
  Nb  Nb7  1  0.113  0.887  0.250  1.0
  Nb  Nb8  1  0.887  0.113  0.750  1.0
  Nb  Nb9  1  0.396  0.249  0.250  1.0
  Nb  Nb10  1  0.500  0.000  0.000  1.0
  Nb  Nb11  1  0.249  0.396  0.750  1.0
  O  O12  1  0.751  0.012  0.249  1.0
  O  O13  1  0.012  0.751  0.749  1.0
  O  O14  1  0.746  0.590  0.406  1.0
  O  O15  1  0.757  0.735  0.093  1.0
  O  O16  1  0.406  0.908  0.280  1.0
  O  O17  1  0.590  0.746  0.906  1.0
  O  O18  1  0.240  0.913  0.093  1.0
  O  O19  1  0.735  0.757  0.593  1.0
  O  O20  1  0.908  0.406  0.780  1.0
  O  O21  1  0.498  0.502  0.250  1.0
  O  O22  1  0.087  0.760  0.407  1.0
  O  O23  1  0.913  0.240  0.593  1.0
  O  O24  1  0.502  0.498  0.750  1.0
  O  O25  1  0.092  0.594  0.220  1.0
  O  O26  1  0.265  0.243  0.407  1.0
  O  O27  1  0.760  0.087  0.907  1.0
  O  O28  1  0.410  0.254  0.094  1.0
  O  O29  1  0.594  0.092  0.720  1.0
  O  O30  1  0.243  0.265  0.907  1.0
  O  O31  1  0.254  0.410  0.594  1.0
  O  O32  1  0.988  0.249  0.251  1.0
  O  O33  1  0.249  0.988  0.751  1.0
[/CIF]
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The compound described by Li2Nb4O11 crystallizes in the monoclinic C2/c space group. Li(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form distorted LiO4 trigonal pyramids that share corners with three equivalent Nb(2)O6 octahedra and  an edgeedge with one Nb(3)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 55-56°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms. In the second Nb site, Nb(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(3)O7 pentagonal bipyramids and corners with six equivalent Li(1)O4 trigonal pyramids. In the third Nb site, Nb(3) is bonded to one O(6), two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted NbO7 pentagonal bipyramids that share corners with two equivalent Nb(2)O6 octahedra and edges with two equivalent Li(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to one Nb(3) and two equivalent Nb(1) atoms. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(3) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fifth O site, O(4) is bonded to one Li(1), one Nb(3), and two equivalent Nb(1) atoms to form corner-sharing OLiNb3 tetrahedra. In the sixth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(2), and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Nb4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.354
_cell_length_b   6.354
_cell_length_c   12.930
_cell_angle_alpha   75.682
_cell_angle_beta   75.682
_cell_angle_gamma   59.249
_symmetry_Int_Tables_number   1
_cell_volume   430.029
_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
  Li  Li0  1  0.855  0.357  0.940  1.0
  Li  Li1  1  0.643  0.145  0.560  1.0
  Li  Li2  1  0.357  0.855  0.440  1.0
  Li  Li3  1  0.145  0.643  0.060  1.0
  Nb  Nb4  1  0.751  0.604  0.250  1.0
  Nb  Nb5  1  0.604  0.751  0.750  1.0
  Nb  Nb6  1  0.000  0.500  0.500  1.0
  Nb  Nb7  1  0.113  0.887  0.250  1.0
  Nb  Nb8  1  0.887  0.113  0.750  1.0
  Nb  Nb9  1  0.396  0.249  0.250  1.0
  Nb  Nb10  1  0.500  0.000  0.000  1.0
  Nb  Nb11  1  0.249  0.396  0.750  1.0
  O  O12  1  0.751  0.012  0.249  1.0
  O  O13  1  0.012  0.751  0.749  1.0
  O  O14  1  0.746  0.590  0.406  1.0
  O  O15  1  0.757  0.735  0.093  1.0
  O  O16  1  0.406  0.908  0.280  1.0
  O  O17  1  0.590  0.746  0.906  1.0
  O  O18  1  0.240  0.913  0.093  1.0
  O  O19  1  0.735  0.757  0.593  1.0
  O  O20  1  0.908  0.406  0.780  1.0
  O  O21  1  0.498  0.502  0.250  1.0
  O  O22  1  0.087  0.760  0.407  1.0
  O  O23  1  0.913  0.240  0.593  1.0
  O  O24  1  0.502  0.498  0.750  1.0
  O  O25  1  0.092  0.594  0.220  1.0
  O  O26  1  0.265  0.243  0.407  1.0
  O  O27  1  0.760  0.087  0.907  1.0
  O  O28  1  0.410  0.254  0.094  1.0
  O  O29  1  0.594  0.092  0.720  1.0
  O  O30  1  0.243  0.265  0.907  1.0
  O  O31  1  0.254  0.410  0.594  1.0
  O  O32  1  0.988  0.249  0.251  1.0
  O  O33  1  0.249  0.988  0.751  1.0
[/CIF]
.