data_global _chemical_name_mineral 'Biotite' loop_ _publ_author_name 'Brigatti M F' 'Davoli P' _journal_name_full 'American Mineralogist' _journal_volume 75 _journal_year 1990 _journal_page_first 305 _journal_page_last 313 _publ_section_title ; Crystal-structure refinement of 1M plutonic biotites sample M32 from a syenite in the Valle del Cervo pluton ; _database_code_amcsd 0001295 _chemical_formula_sum 'Fe Mg2 K (Al Si3) O12 H2' _cell_length_a 5.346 _cell_length_b 9.252 _cell_length_c 10.238 _cell_angle_alpha 90 _cell_angle_beta 100.02 _cell_angle_gamma 90 _cell_volume 498.660 _exptl_crystal_density_diffrn 2.989 _symmetry_space_group_name_H-M 'C 1 2/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' '-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 Fe1 0.00000 0.00000 0.50000 1.00000 Mg2 0.00000 0.33400 0.50000 1.00000 K 0.00000 0.50000 0.00000 1.00000 Al 0.07520 0.16740 0.22620 0.25000 Si 0.07520 0.16740 0.22620 0.75000 O1 0.02360 0.00000 0.16810 1.00000 O2 0.32210 0.23390 0.16950 1.00000 O3 0.13080 0.16730 0.39100 1.00000 O4 0.12930 0.50000 0.39600 1.00000 H 0.01000 0.50000 0.31500 1.00000 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 Fe1 0.01460 0.00954 0.01133 0.00000 0.00430 0.00000 Mg2 0.00786 0.01171 0.01442 0.00000 0.00108 0.00000 K 0.03117 0.03643 0.03502 0.00000 0.00538 0.00000 Al 0.01039 0.00954 0.01184 0.00173 0.00134 0.00095 Si 0.01039 0.00954 0.01184 0.00173 0.00134 0.00095 O1 0.02429 0.02082 0.01493 0.00000 -0.00081 0.00000 O2 0.02148 0.02645 0.01648 -0.00271 0.00350 0.00000 O3 0.01797 0.01431 0.01390 0.00296 0.00108 -0.00331 O4 0.01825 0.01735 0.01802 0.00000 0.00780 0.00000