data_global _chemical_name_mineral 'Alunite' loop_ _publ_author_name 'Hendricks S B' _journal_name_full 'American Mineralogist' _journal_volume 22 _journal_year 1937 _journal_page_first 773 _journal_page_last 784 _publ_section_title ; The crystal structures of alunite and the jarosites ; _database_code_amcsd 0000016 _chemical_formula_sum 'K S2 Al3 O14 H6' _cell_length_a 6.96 _cell_length_b 6.96 _cell_length_c 17.35 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 727.861 _exptl_crystal_density_diffrn 2.835 _symmetry_space_group_name_H-M 'R -3 m' loop_ _space_group_symop_operation_xyz 'x,y,z' '2/3+x,1/3+y,1/3+z' '1/3+x,2/3+y,2/3+z' 'x,x-y,z' '2/3+x,1/3+x-y,1/3+z' '1/3+x,2/3+x-y,2/3+z' 'y,x,-z' '2/3+y,1/3+x,1/3-z' '1/3+y,2/3+x,2/3-z' '-x+y,y,z' '2/3-x+y,1/3+y,1/3+z' '1/3-x+y,2/3+y,2/3+z' '-x,-x+y,-z' '2/3-x,1/3-x+y,1/3-z' '1/3-x,2/3-x+y,2/3-z' '-y,-x,z' '2/3-y,1/3-x,1/3+z' '1/3-y,2/3-x,2/3+z' 'x-y,-y,-z' '2/3+x-y,1/3-y,1/3-z' '1/3+x-y,2/3-y,2/3-z' 'y,-x+y,-z' '2/3+y,1/3-x+y,1/3-z' '1/3+y,2/3-x+y,2/3-z' '-x+y,-x,z' '2/3-x+y,1/3-x,1/3+z' '1/3-x+y,2/3-x,2/3+z' '-x,-y,-z' '2/3-x,1/3-y,1/3-z' '1/3-x,2/3-y,2/3-z' '-y,x-y,z' '2/3-y,1/3+x-y,1/3+z' '1/3-y,2/3+x-y,2/3+z' 'x-y,x,-z' '2/3+x-y,1/3+x,1/3-z' '1/3+x-y,2/3+x,2/3-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z K 0.00000 0.00000 0.00000 S 0.00000 0.00000 0.30500 Al 0.00000 0.50000 0.50000 O1 0.00000 0.00000 0.39300 O2 0.21500 -0.21500 -0.05800 O-H3 0.15000 -0.15000 0.12600