data_1000068
_chemical_name_systematic          'Lithium niobium tungstate -$-alpha'
_chemical_formula_structural       'Li Nb W O6'
_chemical_formula_sum              'Li Nb O6 W'
_publ_section_title
;
Li Nb W O~6~: Crystal structure of its two allotropic forms
;
loop_
_publ_author_name
  'Fourquet, J L'
  'Le Bail, A'
  'Gillet, P A'
_journal_name_full                 'Materials Research Bulletin'
_journal_coden_ASTM                MRBUAC
_journal_volume                    23
_journal_year                      1988
_journal_page_first                1163
_journal_page_last                 1170
_cell_length_a                     4.6819(2)
_cell_length_b                     4.6819(2)
_cell_length_c                     9.2757(5)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       203.3
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P -4 21 m'
_symmetry_Int_Tables_number        113
_symmetry_cell_setting             tetragonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2-x,1/2+y,-z'
  '-x,-y,z'
  '1/2+x,1/2-y,-z'
  '-y,x,-z'
  '1/2+y,1/2+x,z'
  'y,-x,-z'
  '1/2-y,1/2-x,z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Li1+   1.000
  Nb5+   5.000
  W6+    6.000
  O2-   -2.000
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Li1   Li1+   2 c 0. 0.5 0.420(3) 1.  0 d
  Nb1   Nb5+   2 c 0. 0.5 0.0901(3) 0.892(5)  0 d
  W1    W6+    2 c 0. 0.5 0.0901(3) 0.108(5)  0 d
  W2    W6+    2 c 0. 0.5 0.7305(2) 0.892(5)  0 d
  Nb2   Nb5+   2 c 0. 0.5 0.7305(2) 0.108(5)  0 d
  O1    O2-    4 e 0.293(2) 0.793(2) 0.769(2) 1.  0 d
  O2    O2-    4 e 0.298(3) 0.798(3) 0.089(2) 1.  0 d
  O3    O2-    4 e 0.302(2) 0.802(2) 0.381(2) 1.  0 d
_refine_ls_R_factor_all            0.0974