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 = 100 C ; _database_code_amcsd 0003723 _chemical_formula_sum '(Si2.685 Al2.315) O12.37 Na1.462 Ca.474 H4.74' _cell_length_a 13.0666 _cell_length_b 13.0666 _cell_length_c 6.6632 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1137.648 _exptl_crystal_density_diffrn 2.296 _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 0.00830 AlT1 0.00000 0.00000 0.00000 0.46300 0.00830 SiT2 0.05600 0.13360 0.62200 0.53700 0.00830 AlT2 0.05600 0.13360 0.62200 0.46300 0.00830 O1 0.38880 0.25000 0.12500 1.00000 0.01550 O2 0.13510 0.05900 0.48570 1.00000 0.01550 O3 0.05160 0.09430 0.86640 1.00000 0.01550 Na 0.69230 0.25000 0.12500 0.73100 0.01950 Ca 0.69230 0.25000 0.12500 0.23700 0.01950 Wat4 0.12870 0.25000 0.12500 1.00000 0.02300 Wat5 0.89500 0.25000 0.12500 0.18500 0.02300