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 = 200 C ; _database_code_amcsd 0003724 _chemical_formula_sum '(Si2.685 Al2.315) O12.102 Na1.462 Ca.474 H4.204' _cell_length_a 12.9815 _cell_length_b 12.9815 _cell_length_c 6.6808 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1125.844 _exptl_crystal_density_diffrn 2.291 _symmetry_space_group_name_H-M 'I -4 2 d' loop_ _space_group_symop_operation_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 0.01190 AlT1 0.00000 0.00000 0.00000 0.46300 0.01190 SiT2 0.05640 0.13400 0.62240 0.53700 0.01190 AlT2 0.05640 0.13400 0.62240 0.46300 0.01190 O1 0.38420 0.25000 0.12500 1.00000 0.02060 O2 0.13560 0.05910 0.48810 1.00000 0.02060 O3 0.05330 0.09500 0.86500 1.00000 0.02060 Na 0.69250 0.25000 0.12500 0.73100 0.02400 Ca 0.69250 0.25000 0.12500 0.23700 0.02400 Wat4 0.12580 0.25000 0.12500 1.00000 0.02700 Wat5 0.94200 0.25000 0.12500 0.05100 0.02700