data_1001356
_chemical_name_systematic          'Potassium niobium uranium oxide'
_chemical_formula_structural       'K Nb U O6'
_chemical_formula_sum              'K Nb O6 U'
_publ_section_title
;
Synthese et structure de trois niobouranates d'ions monovalents: Tl
Nb~2~ U~2~ O~11.5~, K Nb U O~6~, et Rb Nb U O~6~
;
_publ_author_name                  'Gasperin, M'
_journal_name_full                 'Journal of Solid State Chemistry'
_journal_coden_ASTM                JSSCBI
_journal_volume                    67
_journal_year                      1987
_journal_page_first                219
_journal_page_last                 224
_cell_length_a                     7.579(2)
_cell_length_b                     11.321(4)
_cell_length_c                     15.259(5)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       1309.3
_cell_formula_units_Z              8
_exptl_crystal_density_meas        4.73
_symmetry_space_group_name_H-M     'P c a b'
_symmetry_Int_Tables_number        61
_symmetry_cell_setting             orthorhombic
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2+x,-y,1/2-z'
  '-x,1/2-y,1/2+z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,y,1/2+z'
  'x,1/2+y,1/2-z'
  '1/2+x,1/2-y,z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  U6+    6.000
  Nb5+   5.000
  K1+    1.000
  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
  U1    U6+    8 c 0.1248(2) 0.0228(1) 0.2593(1) 1.  0 d
  Nb1   Nb5+   8 c 0.3857(4) 0.7499(2) 0.1453(2) 1.  0 d
  K1    K1+    8 c 0.3651(38) 0.2494(12) 0.0912(11) 0.64  0 d
  K2    K1+    8 c 0.3625(34) 0.0742(18) 0.0200(17) 0.36  0 d
  O1    O2-    8 c 0.6287(29) 0.0564(15) 0.1422(12) 1.  0 d
  O2    O2-    8 c 0.1240(33) 0.1047(17) 0.1614(12) 1.  0 d
  O3    O2-    8 c 0.1228(28) 0.7068(13) 0.1630(13) 1.  0 d
  O4    O2-    8 c 0.3370(29) 0.9032(19) 0.2020(19) 1.  0 d
  O5    O2-    8 c 0.9148(24) 0.8977(18) 0.2074(21) 1.  0 d
  O6    O2-    8 c 0.3645(174) 0.7421(23) 0.0340(16) 1.  0 d
_refine_ls_R_factor_all            0.082