data_global
_chemical_name_mineral 'Lukechangite-(Ce)'
loop_
_publ_author_name
'Grice J D'
'Chao G Y'
_journal_name_full 'American Mineralogist'
_journal_volume 82 
_journal_year 1997
_journal_page_first 1255
_journal_page_last 1260
_publ_section_title
;
 Lukechangite-(Ce), a new rare-earth-fluorocarbonate mineral from
 Mont Saint-Hilaire, Quebec
 Note: U(1,2) for Na1, O1, O2 and F changed to match symmetry constraints.
 Note: U(2,3) for O2 changed to match symmetry constraints.
;
_database_code_amcsd 0001952
_chemical_formula_sum 'Na3 Ce2 C4 O12 F'
_cell_length_a 5.0612
_cell_length_b 5.0612
_cell_length_c 22.820
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 506.236
_exptl_crystal_density_diffrn      3.990
_symmetry_space_group_name_H-M 'P 63/m m c'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-x+y,1/2+z'
  'x,x-y,1/2-z'
  '-x+y,-x,1/2-z'
  'x-y,x,1/2+z'
  '-y,-x,z'
  'y,x,-z'
  'y,-x+y,-z'
  '-y,x-y,z'
  'x-y,-y,1/2+z'
  '-x+y,y,1/2-z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  'x,x-y,z'
  '-x,-x+y,-z'
  'x-y,x,-z'
  '-x+y,-x,z'
  'y,x,1/2+z'
  '-y,-x,1/2-z'
  '-y,x-y,1/2-z'
  'y,-x+y,1/2+z'
  '-x+y,y,z'
  'x-y,-y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Nal   0.33333   0.66667   0.47770
Na2   0.00000   0.00000   0.25000
Ce   0.66667   0.33333   0.35447
C1   0.00000   0.00000   0.43580
C2   0.33333   0.66667   0.32390
O1   0.28960   0.14480   0.43750
O2   0.18705   0.37410   0.32410
F   0.66667   0.33333   0.25000
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Nal 0.02650 0.02650 0.02390 0.01325 0.00000 0.00000
Na2 0.02760 0.02760 0.00830 0.01380 0.00000 0.00000
Ce 0.00920 0.00920 0.00470 0.00460 0.00000 0.00000
C1 0.01230 0.01230 0.01210 0.00610 0.00000 0.00000
C2 0.00980 0.00980 0.00740 0.00490 0.00000 0.00000
O1 0.01270 0.07830 0.01160 0.00635 0.00020 0.00010
O2 0.01590 0.01050 0.01980 0.00525 -0.00050 -0.00100
F 0.02770 0.02770 0.01170 0.01385 0.00000 0.00000