data_global
_amcsd_formula_title 'Nb4 O21 Sr3 Ti4'
loop_
_publ_author_name
'Saurel C'
'Groult D'
'Raveau B'
_journal_name_full 'Materials Research Bulletin'
_journal_volume 12 
_journal_year 1977
_journal_page_first 629
_journal_page_last 635
_publ_section_title
;
 Etude du comportement de l'antimoine V et du strontium dans les oxydes
 a structure en cages du type A3 M8 O21
 _cod_database_code 1001278
;
_database_code_amcsd 0014258
_chemical_formula_sum 'Sr3 (Ti4 Nb4) O21'
_cell_length_a 8.992
_cell_length_b 8.992
_cell_length_c 11.605
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 812.622
_exptl_crystal_density_diffrn      4.749
_symmetry_space_group_name_H-M 'P 63/m c m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-x+y,z'
  'x,x-y,-z'
  '-x+y,-x,1/2-z'
  'x-y,x,1/2+z'
  '-y,-x,1/2+z'
  'y,x,1/2-z'
  'y,-x+y,-z'
  '-y,x-y,z'
  'x-y,-y,z'
  '-x+y,y,-z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  'x,x-y,1/2+z'
  '-x,-x+y,1/2-z'
  'x-y,x,-z'
  '-x+y,-x,z'
  'y,x,z'
  '-y,-x,-z'
  '-y,x-y,1/2-z'
  'y,-x+y,1/2+z'
  '-x+y,y,1/2+z'
  'x-y,-y,1/2-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Sr1   0.59500   0.00000   0.25000   1.00000
Ti1   0.24400   0.00000   0.09290   0.50000
Nb1   0.24400   0.00000   0.09290   0.50000
Nb2   0.33333   0.66667   0.00000   0.50000
Ti2   0.33333   0.66667   0.00000   0.50000
O1   0.24700   0.00000   0.25000   1.00000
O2   0.79700   0.00000   0.07800   1.00000
O3   0.17000   0.50000   0.11200   1.00000