data_global
_chemical_name_mineral 'Nasonite'
loop_
_publ_author_name
'Giuseppetti G'
'Rossi G'
'Tadini C'
_journal_name_full 'American Mineralogist'
_journal_volume 56
_journal_year 1971
_journal_page_first 1174
_journal_page_last 1179
_publ_section_title
;
 The crystal structure of nasonite
;
_database_code_amcsd 251
_chemical_formula_sum 'Pb6 Ca4 Cl2 Si6 O21'
_cell_length_a 10.08
_cell_length_b 10.08
_cell_length_c 13.27
_cell_angle_alpha 90.0
_cell_angle_beta 90.0
_cell_angle_gamma 120.0
_cell_volume 1167.677
_exptl_crystal_density_diffrn  5.628
_symmetry_space_group_name_H-M 'P 63/m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x+y,-x,1/2-z'
  'x-y,x,1/2+z'
  'y,-x+y,-z'
  '-y,x-y,z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  'x-y,x,-z'
  '-x+y,-x,z'
  '-y,x-y,1/2-z'
  'y,-x+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_U_iso_or_equiv
Pb   0.25801  0.26493  0.10862  0.01824
Ca1   0.333333  0.666667  0.9936  0.01241
Ca2   0.333333  0.666667  0.25  0.01203
Ca3   0.666667  0.333333  0.25  0.00975
Cl1   0.0  0.0  0.25  0.0271
Cl2   0.0  0.0  0.0  0.02558
Si   0.0259  0.4198  0.3644  0.00659
O1   0.071  0.3291  0.4444  0.02672
O2   0.8588  0.3949  0.6208  0.01368
O3   0.8545  0.3748  0.3725  0.02166
O4   0.0714  0.383  0.25  0.01748