data_global
_chemical_name_mineral 'Gonnardite'
loop_
_publ_author_name
'Lee Y'
'Hriljac J A'
'Vogt T'
_journal_name_full 'American Mineralogist'
_journal_volume 90 
_journal_year 2005
_journal_page_first 247
_journal_page_last 251
_publ_section_title
;
 Variable-temperature structural studies of tetranatrolite from Mt. Saint-Hilaire:
 Synchrotron X-ray powder diffraction and Rietveld analysis
 Sample: at ambient conditions
;
_chemical_formula_sum '(Si2.685 Al2.315) O12.74 Na1.462 Ca.474 H8'
_cell_length_a 13.1988
_cell_length_b 13.1988
_cell_length_c 6.6288
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1154.792
_exptl_crystal_density_diffrn      2.314
_symmetry_space_group_name_H-M 'I -4 2 d'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  '1/2-y,-x,3/4+z'
  '-y,1/2-x,1/4+z'
  'y,-x,-z'
  '1/2+y,1/2-x,1/2-z'
  '-x,1/2+y,1/4-z'
  '1/2-x,+y,3/4-z'
  '-x,-y,z'
  '1/2-x,1/2-y,1/2+z'
  '1/2+y,x,3/4+z'
  '+y,1/2+x,1/4+z'
  '-y,x,-z'
  '1/2-y,1/2+x,1/2-z'
  'x,1/2-y,1/4-z'
  '1/2+x,-y,3/4-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
SiT1   0.00000   0.00000   0.00000   0.53700   0.00800
AlT1   0.00000   0.00000   0.00000   0.46300   0.00800
SiT2   0.05500   0.13260   0.62100   0.53700   0.00800
AlT2   0.05500   0.13260   0.62100   0.46300   0.00800
O1   0.39180   0.25000   0.12500   1.00000   0.01200
O2   0.13390   0.06070   0.47800   1.00000   0.01200
O3   0.05260   0.09510   0.86620   1.00000   0.01200
Na   0.69230   0.25000   0.12500   0.73100   0.02680
Ca   0.69230   0.25000   0.12500   0.23700   0.02680
Wat4   0.12770   0.25000   0.12500   1.00000   0.03800
Wat5   0.87500   0.25000   0.12500   0.37000   0.03800