data_global _chemical_name_mineral 'Natrolite' loop_ _publ_author_name 'Baur W H' 'Kassner D' 'Kim C' 'Sieber N H W' _journal_name_full 'European Journal of Mineralogy' _journal_volume 2 _journal_year 1990 _journal_page_first 761 _journal_page_last 769 _publ_section_title ; Flexibility and distortion of the framework of natrolite: crystal structures of ion-exchanged natrolites Sample: K-natrolite, KK ; _database_code_amcsd 0006393 _chemical_formula_sum 'K2 Al2 Si3 O12 H4' _cell_length_a 19.27 _cell_length_b 19.66 _cell_length_c 6.469 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 2450.769 _exptl_crystal_density_diffrn 2.236 _symmetry_space_group_name_H-M 'F d d 2' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2+y,1/2+z' '1/2+x,y,1/2+z' '1/2+x,1/2+y,z' '1/4+x,1/4-y,1/4+z' '1/4+x,3/4-y,3/4+z' '3/4+x,1/4-y,3/4+z' '3/4+x,3/4-y,1/4+z' '1/4-x,1/4+y,1/4+z' '1/4-x,3/4+y,3/4+z' '3/4-x,1/4+y,3/4+z' '3/4-x,3/4+y,1/4+z' '-x,1/2-y,1/2+z' '-x,-y,+z' '1/2-x,1/2-y,+z' '1/2-x,-y,1/2+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z K 0.21850 0.53100 0.12100 Al 0.20230 0.33590 0.85900 Si1 0.00000 0.00000 0.00000 Si2 0.16140 0.20280 0.62000 O1 0.04180 0.05410 0.85900 O2 0.16330 0.41550 0.86000 O3 0.15410 0.27890 0.71300 O4 0.28590 0.34160 0.76100 O5 0.94470 0.04090 0.14100 Wat 0.17430 0.42410 0.37000