data_2002944
_journal_name_full     'Acta Crystallographica, Section B'
_journal_year     1999
_journal_volume     B55
_journal_page_first     24
_journal_page_last     30
_chemical_formula_moiety     'Na1 Nb1 O3 '
_chemical_formula_sum     'Na1 Nb1 O3  '
_chemical_formula_weight     ?
_symmetry_cell_setting     tetragonal
_symmetry_space_group_name_H-M     'P 4/m b m'
_symmetry_space_group_name_Hall     '-P 4 2ab'
loop_
    _symmetry_equiv_pos_as_xyz
    'x, y, z'
    '-y, x, z'
    '-x, -y, z'
    'y, -x, z'
    'x+1/2, -y+1/2, -z'
    '-x+1/2, y+1/2, -z'
    'y+1/2, x+1/2, -z'
    '-y+1/2, -x+1/2, -z'
_cell_length_a     5.56896(2)
_cell_length_b     5.56896(2)
_cell_length_c     3.94408(2)
_cell_angle_alpha     90.00
_cell_angle_beta     90.00
_cell_angle_gamma     90.00
_cell_volume     ?
_cell_formula_units_Z     2
_cell_measurement_temperature     888
_diffrn_radiation_type     neutron
_diffrn_radiation_wavelength     ?
_refine_ls_R_factor_all     ?
loop_
    _atom_site_label
    _atom_site_fract_x
    _atom_site_fract_y
    _atom_site_fract_z
    Nb .0 .0 .0
    Na .0 .5 .5
    O1 .0 .0 .5
    O2 .27190(10)
                .22810(10)
                         .0