data_global
_chemical_name_mineral 'Lueshite'
loop_
_publ_author_name
'Johnston K E'
'Tang C C'
'Parker J E'
'Knight K S'
'Lightfoot P'
'Ashbrook S E'
_journal_name_full 'Journal of the American Chemical Society'
_journal_volume 132 
_journal_year 2010
_journal_page_first 8732
_journal_page_last 8746
_publ_section_title
;
 The polar phase of NaNbO3: a combined study by powder diffraction,
 solid-state NMR and first-principles calculations
 Note: this is a polymorph of lueshite
;
_database_code_amcsd 0018685
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Nb Na O3'
_cell_length_a 5.571
_cell_length_b 7.766
_cell_length_c 5.513
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 238.517
_exptl_crystal_density_diffrn      4.564
_symmetry_space_group_name_H-M 'P 21 m a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,y,-z'
  'x,-y,z'
  '1/2+x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Nb   0.26250   0.25000   0.24660   0.00200
Na   0.25960   0.00000   0.74810   0.00500
Na   0.29150   0.50000   0.73270   0.02240
O1   0.24090   0.00000   0.31240   0.00530
O2   0.22570   0.50000   0.19280   0.00370
O3   0.01310   0.27900   0.52720   0.01840
O4  -0.04900   0.21970   0.03600   0.00610