data_global _chemical_name_mineral 'Muscovite' loop_ _publ_author_name 'Tomita K' 'Shiraki K' 'Kawano M' _journal_name_full 'Clay Science' _journal_volume 10 _journal_year 1998 _journal_page_first 423 _journal_page_last 441 _publ_section_title ; Crystal structure of dehydroxylated 2M1 sericite and its relationship with mixed-layer mica/smectite Sample: unheated ; _database_code_amcsd 0012229 _chemical_formula_sum 'K.727 Na.17 Ca.01 Al2.752 Fe.03 Mg.022 Si3.128 Ti.02 O12 H2' _cell_length_a 5.1909 _cell_length_b 9.0048 _cell_length_c 20.1170 _cell_angle_alpha 90 _cell_angle_beta 95.773 _cell_angle_gamma 90 _cell_volume 935.560 _exptl_crystal_density_diffrn 2.783 _symmetry_space_group_name_H-M 'C 1 2/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '-x,y,1/2-z' '1/2-x,1/2+y,1/2-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 _atom_site_U_iso_or_equiv K1 0.00000 0.10400 0.25000 0.72700 0.04243 NaK1 0.00000 0.10400 0.25000 0.17000 0.04243 CaK1 0.00000 0.10400 0.25000 0.01000 0.04243 AlM2 0.24900 0.08500 0.00010 0.93300 0.00773 FeM2 0.24900 0.08500 0.00010 0.01500 0.00773 MgM2 0.24900 0.08500 0.00010 0.01100 0.00773 SiT1 0.45900 0.92900 0.13480 0.77700 0.02698 AlT1 0.45900 0.92900 0.13480 0.22000 0.02698 TiT1 0.45900 0.92900 0.13480 0.00500 0.02698 SiT2 0.45500 0.25900 0.13480 0.78700 0.02698 AlT2 0.45500 0.25900 0.13480 0.22300 0.02698 TiT2 0.45500 0.25900 0.13480 0.00500 0.02698 O1 0.46800 0.94600 0.05540 1.00000 0.02318 O2 0.38500 0.24900 0.05500 1.00000 0.02318 O3 0.41600 0.09800 0.16740 1.00000 0.02318 O4 0.25500 0.80800 0.15710 1.00000 0.02318 O5 0.25100 0.36900 0.16940 1.00000 0.02318 O-H6 0.44400 0.56800 0.04840 1.00000 0.02318