data_global
_amcsd_formula_title 'Cs8 Nb10 O41 Si6'
loop_
_publ_author_name
'Crosnier M'
'Pagnoux C'
'Guyomard D'
'Verbaere A'
'Piffard Y'
'Tournoux M'
_journal_name_full 'European Journal of Solid State and Inorganic Chemistry'
_journal_volume 28 
_journal_year 1991
_journal_page_first 971
_journal_page_last 981
_publ_section_title
;
 The crystal structure of a novel cyclotrisilicate: Cs8Nb10O23(Si3O9)2.
 Its relationship with the pyrochlore and benitoite types
 _cod_database_code 1000469
;
_database_code_amcsd 0012545
_chemical_formula_sum 'Cs4 Nb5 Si3 O20.502'
_cell_length_a 7.342
_cell_length_b 7.342
_cell_length_c 22.16599
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 1034.776
_exptl_crystal_density_diffrn      4.520
_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
_atom_site_occupancy
Cs1   0.33333   0.66667   0.15558   1.00000
Cs2   0.00000   0.00000   0.09183   1.00000
Nb1   0.50000   0.00000   0.00000   1.00000
Nb2   0.33333   0.66667   0.63573   1.00000
Si1   0.86230   0.72460   0.25000   1.00000
O1   0.11700   0.23400   0.25000   1.00000
O2   0.20900   0.41800   0.48160   0.91700
O3   0.54570   0.09140   0.08630   1.00000
O4   0.20570   0.41140   0.68980   1.00000
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
Cs1 0.03110 0.03110 0.02760 0.01560 0.00000 0.00000
Cs2 0.03450 0.03450 0.02330 0.01730 0.00000 0.00000
Nb1 0.02640 0.02140 0.02350 0.01070 -0.00030 -0.00060
Nb2 0.01760 0.01760 0.01580 0.00880 0.00000 0.00000
Si1 0.00110 0.00040 0.00170 0.00020 0.00000 0.00000
O1 0.00100 0.00070 0.00560 0.00040 0.00000 0.00000
O2 0.00320 0.00340 0.00310 0.00170 -0.00030 -0.00060
O3 0.00430 0.00160 0.00190 0.00080 -0.00020 -0.00040
O4 0.00480 0.00170 0.00180 0.00090 0.00030 0.00060