data_global _chemical_name_mineral 'Fluorapophyllite-(K)' loop_ _publ_author_name 'Stahl K' _journal_name_full 'European Journal of Mineralogy' _journal_volume 5 _journal_year 1993 _journal_page_first 845 _journal_page_last 849 _publ_section_title ; A neutron powder diffraction study of partially dehydrated fluorapophyllite, KCa4Si8O20F*6.9H2O ; _database_code_amcsd 0019990 _chemical_compound_source 'Poona, India' _chemical_formula_sum 'F K Ca4 Si8 O26.88 H13.76' _cell_length_a 8.9639 _cell_length_b 8.9639 _cell_length_c 15.754 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1265.857 _exptl_crystal_density_diffrn 2.327 _symmetry_space_group_name_H-M 'P 4/m n c' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2-y,1/2-x,1/2+z' '1/2+y,1/2+x,1/2-z' 'y,-x,-z' '-y,x,z' '1/2+x,1/2-y,1/2+z' '1/2-x,1/2+y,1/2-z' 'x,y,-z' '-x,-y,z' '1/2+y,1/2+x,1/2+z' '1/2-y,1/2-x,1/2-z' '-y,x,-z' 'y,-x,z' '1/2-x,1/2+y,1/2+z' '1/2+x,1/2-y,1/2-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy F 0.00000 0.00000 0.00000 1.00000 K 0.00000 0.00000 0.50000 1.00000 Ca 0.11500 0.24020 0.00000 1.00000 Si 0.23170 0.08730 0.19170 1.00000 O1 0.36240 0.13760 0.25000 1.00000 O2 0.08940 0.19150 0.21590 1.00000 O3 0.26630 0.10210 0.09230 1.00000 O4 0.21320 0.44890 0.09030 0.69000 O5 0.18480 0.48780 0.00000 0.34000 H1 0.44650 0.17220 0.08940 0.69000 H2 0.22090 0.42570 0.14920 0.69000 H3 0.15740 0.55050 0.03660 0.34000