#------------------------------------------------------------------------------ #$Date: 2008-01-14 00:15:36 +0200 (Mon, 14 Jan 2008) $ #$Revision: 14 $ #$URL: file:///home/coder/svn-repositories/cod/cif/1/1000038.cif $ #------------------------------------------------------------------------------ # # This file is available in the Crystallography Open Database (COD), # http://www.crystallography.net/ # # All data on this site have been placed in the public domain by the # contributors. # data_Biotite _chemical_name_systematic ; Potassium iron dimagnesium phyllo-alumotrisilicate dihydroxide ; _chemical_name_mineral 'Biotite' _chemical_compound_source 'from Valle de Cervo, Vercelli, Italy' _chemical_formula_structural 'K Fe Mg2 (Al Si3 O10) (O H)2' _chemical_formula_analytical ; (Na.021 K.908) (Al.015 Fe1.217 Mg1.386 Mn.015 Ti.25 Li.006) (Al1.258 Si2.742 O10.318) (O H)1.628 Cl0.053 ; _chemical_formula_sum 'H2 Al Fe K Mg2 O12 Si3' _publ_section_title ; Crystal structure refinement of 1M plutonic biotites ; loop_ _publ_author_name 'Brigatti, M F' 'Davoli, P' _journal_name_full 'American Mineralogist' _journal_coden_ASTM AMMIAY _journal_volume 75 _journal_year 1990 _journal_page_first 305 _journal_page_last 313 _cell_length_a 5.345(1) _cell_length_b 9.258(2) _cell_length_c 10.222(2) _cell_angle_alpha 90 _cell_angle_beta 100.23(2) _cell_angle_gamma 90 _cell_volume 497.8 _cell_formula_units_Z 2 _symmetry_space_group_name_H-M 'C 1 2/m 1' _symmetry_Int_Tables_number 12 _symmetry_cell_setting monoclinic loop_ _symmetry_equiv_pos_as_xyz 'x,y,z' 'x,-y,z' '-x,-y,-z' '-x,y,-z' '1/2+x,1/2+y,z' '1/2+x,1/2-y,z' '1/2-x,1/2-y,-z' '1/2-x,1/2+y,-z' loop_ _atom_type_symbol _atom_type_oxidation_number O2- -2.000 Mg2+ 2.000 Fe2+ 2.000 K1+ 1.000 Al3+ 3.000 Si4+ 4.000 H1+ 1.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_symmetry_multiplicity _atom_site_Wyckoff_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy _atom_site_attached_hydrogens _atom_site_calc_flag O1 O2- 4 i 0.0267(6) 0. 0.1687(3) 1. 0 d O2 O2- 8 j 0.3195(4) 0.2361(3) 0.1681(2) 1. 0 d O3 O2- 8 j 0.1316(3) 0.1677(2) 0.3909(2) 1. 0 d O4 O2- 4 i 0.1291(5) 0.5 0.3947(3) 1. 0 d Mg1 Mg2+ 4 h 0. 0.3347(1) 0.5 1. 0 d Fe1 Fe2+ 2 c 0. 0. 0.5 1. 0 d K1 K1+ 2 b 0. 0.5 0. 1. 0 d Al1 Al3+ 8 j 0.0748(1) 0.1669(1) 0.2257(1) 0.25 0 d Si1 Si4+ 8 j 0.0748(1) 0.1669(1) 0.2257(1) 0.75 0 d H1 H1+ 4 i 0.09 0.5 0.315 1. 0 d _refine_ls_R_factor_all 0.021