data_global _chemical_name_mineral 'Fluoro-richterite' loop_ _publ_author_name 'Cameron M' 'Sueno S' 'Papike J J' 'Prewitt C T' _journal_name_full 'American Mineralogist' _journal_volume 68 _journal_year 1983 _journal_page_first 924 _journal_page_last 943 _publ_section_title ; High temperature crystal chemistry of K and Na fluor-richterites Note: sample K, T = 400 C ; _database_code_amcsd 0000918 _chemical_formula_sum 'Si8 Mg5 (Na2 Ca2) K2 O22 F2' _cell_length_a 10.041 _cell_length_b 18.056 _cell_length_c 5.272 _cell_angle_alpha 90 _cell_angle_beta 105.83 _cell_angle_gamma 90 _cell_volume 919.566 _exptl_crystal_density_diffrn 3.397 _symmetry_space_group_name_H-M 'I 1 2/m 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,1/2+z' 'x,-y,z' '1/2+x,1/2-y,1/2+z' '-x,y,-z' '1/2-x,1/2+y,1/2-z' '-x,-y,-z' '1/2-x,1/2-y,1/2-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Si1 0.27618 0.91555 0.97700 Si2 0.28542 0.82890 0.48069 Mg1 0.00000 0.91021 0.50000 Mg2 0.00000 0.82016 0.00000 Mg3 0.00000 0.00000 0.00000 Na 0.00000 0.72220 0.50000 Ca 0.00000 0.72220 0.50000 K 0.48221 0.00000 0.52531 O1 0.11118 0.91472 0.89180 O2 0.11803 0.83100 0.39241 F3 0.10185 0.00000 0.38775 O4 0.36077 0.75222 0.56054 O5 0.34368 0.87076 0.25059 O6 0.34039 0.88204 0.75026 O7 0.33433 0.00000 0.02971 loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 Si1 0.01017 0.01007 0.00961 0.00057 0.00310 0.00002 Si2 0.00994 0.01075 0.00916 0.00137 0.00160 0.00035 Mg1 0.01424 0.01272 0.01134 0.00000 0.00308 0.00000 Mg2 0.01391 0.01406 0.01398 0.00000 0.00140 0.00000 Mg3 0.01550 0.01098 0.01090 0.00000 0.00315 0.00000 Na 0.03198 0.01739 0.01766 0.00000 -0.00458 0.00000 Ca 0.03198 0.01739 0.01766 0.00000 -0.00458 0.00000 K 0.09164 0.04988 0.04897 0.00000 -0.03619 0.00000 O1 0.01126 0.01498 0.01280 0.00189 0.00123 -0.00160 O2 0.01229 0.01924 0.01258 0.00040 0.00228 -0.00279 F3 0.01825 0.02294 0.01702 0.00000 0.00180 0.00000 O4 0.02107 0.01671 0.02168 0.01007 0.00382 0.00310 O5 0.01647 0.01939 0.01359 -0.00027 0.00285 0.00520 O6 0.01657 0.02367 0.01326 -0.00020 0.00416 -0.00662 O7 0.02093 0.00902 0.02588 0.00000 0.00101 0.00000