data_global _chemical_name_mineral 'Rhodesite' loop_ _publ_author_name 'Hesse K F' 'Liebau F' 'Merlino S' _journal_name_full 'Zeitschrift fur Kristallographie' _journal_volume 199 _journal_year 1992 _journal_page_first 25 _journal_page_last 48 _publ_section_title ; Crystal structure of rhodesite, HK1-xNax+2yCa2-y(lB,3,22)(Si8O19)*(6-z)H2O, from three localities and its relation to other silicates with dreier double layers ; _database_code_amcsd 0011015 _chemical_compound_source 'San Venanzo, Italy' _chemical_formula_sum 'K.25 Ca.5 Si6 O17.805 H5.11' _cell_length_a 23.428 _cell_length_b 6.557 _cell_length_c 7.064 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1085.153 _exptl_crystal_density_diffrn 1.495 _symmetry_space_group_name_H-M 'P m a m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,-z' '-x,-y,z' '1/2-x,y,z' '1/2+x,-y,-z' '1/2+x,-y,z' '1/2-x,y,-z' '-x,-y,-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 K 0.25000 0.44870 0.00000 0.25000 0.03600 Ca1 0.00000 0.50000 0.00000 0.25000 0.01500 Ca2 0.00000 0.50000 0.50000 0.25000 0.00900 Si1 0.11700 0.28920 0.21980 1.00000 0.00800 Si2 0.18370 0.54170 0.50000 0.50000 0.00800 Si3 0.10240 0.93060 0.50000 0.50000 0.00600 O1 0.05930 0.40840 0.25000 1.00000 0.01600 O2 0.17220 0.40770 0.31110 1.00000 0.01500 O3 0.11650 0.06160 0.31200 1.00000 0.02400 O4 0.13510 0.25550 0.00000 0.50000 0.01100 O5 0.14600 0.73940 0.50000 0.50000 0.01700 O6 0.03750 0.85830 0.50000 0.50000 0.02400 O7 0.25000 0.60490 0.50000 0.25000 0.01300 Wat8 0.03790 0.83150 0.00000 0.50000 0.09900 Wat9 0.33170 0.77920 0.00000 0.50000 0.07400 Wat10 0.25000 0.02040 0.18740 0.25000 0.10200 Wat11 0.25000 0.05200 0.50000 0.05500 0.09000