data_global _chemical_name_mineral 'Phlogopite' loop_ _publ_author_name 'Hendricks S B' 'Jefferson M E' _journal_name_full 'American Mineralogist' _journal_volume 24 _journal_year 1939 _journal_page_first 729 _journal_page_last 771 _publ_section_title ; Polymorphism of the micas with optical measurements Note: Biotite group ; _database_code_amcsd 24 _chemical_formula_sum 'K Mg3 (Si3 Al) O11 (F H)' _cell_length_a 5.32 _cell_length_b 9.21 _cell_length_c 10.16 _cell_angle_alpha 90.0 _cell_angle_beta 100.03 _cell_angle_gamma 90.0 _cell_volume 490.203 _exptl_crystal_density_diffrn 2.84 _symmetry_space_group_name_H-M 'C 1 m 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,z' '1/2+x,1/2-y,z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy K 0.45 0.5 0.84 1.0 Mg1 0.44 0.33 0.34 1.0 Mg2 0.44 0.0 0.34 1.0 Si1 0.02 0.33 0.06 0.75 Si2 0.37 0.17 0.62 0.75 Al1 0.02 0.33 0.06 0.25 Al2 0.37 0.17 0.62 0.25 O1 0.25 0.25 0.0 1.0 O2 0.08 0.33 0.22 1.0 O3 0.32 0.17 0.46 1.0 O4 0.14 0.25 0.68 1.0 O5 0.0 0.5 0.0 1.0 O6 0.39 0.0 0.68 1.0 O-H1 0.08 0.0 0.22 0.5 O-H2 0.32 0.5 0.46 0.5 F1 0.08 0.0 0.22 0.5 F2 0.32 0.5 0.46 0.5