data_1011290
_chemical_name_systematic          'Diammonium hexafluorosilicate'
_chemical_name_mineral             'Bararite'
_chemical_formula_structural       '(N H4)2 (Si F6)'
_chemical_formula_sum              'H8 F6 N2 Si'
_publ_section_title
;
Das Kristallgitter von Ammoniumhexafluorosilikat (N H4)2 Si F6
;
loop_
_publ_author_name
  'Gossner, B'
  'Kraus, O'
_journal_name_full
;
Zeitschrift fuer Kristallographie, Kristallgeometrie, Kristallphysik,
Kristallchemie (-144,1977)
;
_journal_coden_ASTM                ZEKGAX
_journal_volume                    88
_journal_year                      1934
_journal_page_first                223
_journal_page_last                 225
_cell_length_a                     5.76
_cell_length_b                     5.76
_cell_length_c                     4.77
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  120
_cell_volume                       137.1
_cell_formula_units_Z              1
_symmetry_space_group_name_H-M     'P -3 m 1'
_symmetry_Int_Tables_number        164
_symmetry_cell_setting             trigonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-y,x-y,z'
  'y-x,-x,z'
  '-y,-x,z'
  'x,x-y,z'
  'y-x,y,z'
  '-x,-y,-z'
  'y,y-x,-z'
  'x-y,x,-z'
  'y,x,-z'
  '-x,y-x,-z'
  'x-y,-y,-z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Si4+   4.000
  F1-   -1.000
  N3-   -3.000
  H1+    1.000
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
  Si1   Si4+   1 a 0. 0. 0. 1.  0 d
  F1    F1-    6 i 0.136 -0.136 0.2 1.  0 d
  N1    N3-    2 d 0.3333 0.6667 -0.25 1.  0 d
  H1    H1+    2 ? -1. -1. -1. 4.  0 dum