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: T = 300 C, phase I
;
_chemical_formula_sum '(Si2.685 Al2.315) O12 Na1.462 Ca.474 H.204'
_cell_length_a 12.9202
_cell_length_b 12.9202
_cell_length_c 6.6950
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 1117.607
_exptl_crystal_density_diffrn      2.274
_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   0.04800
AlT1   0.00000   0.00000   0.00000   0.46300   0.04800
SiT2   0.05100   0.13600   0.62500   0.53700   0.04800
AlT2   0.05100   0.13600   0.62500   0.46300   0.04800
O1   0.39200   0.25000   0.12500   1.00000   0.02600
O2   0.12600   0.06900   0.47600   1.00000   0.02600
O3   0.04500   0.09700   0.86200   1.00000   0.02600
Na   0.68700   0.25000   0.12500   0.73100   0.04600
Ca   0.68700   0.25000   0.12500   0.23700   0.04600
Wat4   0.13400   0.25000   0.12500   1.00000   0.04600