data_global _chemical_name_mineral 'Phengite' loop_ _publ_author_name 'Pavese A' 'Ferraris G' 'Pischedda V' 'Ibberson R' _journal_name_full 'European Journal of Mineralogy' _journal_volume 11 _journal_year 1999 _journal_page_first 309 _journal_page_last 320 _publ_section_title ; Tetrahedral order in phengite 2M_1 upon heating, from powder neutron diffraction, and thermodynamic consequences Sample: T = 873 K ; _database_code_amcsd 0006769 _chemical_formula_sum 'K.94 Na.03 Al2.43 Mg.04 Fe.34 Si3.24 O11.88 F.12 H1.88' _cell_length_a 5.23899 _cell_length_b 9.1048 _cell_length_c 20.2440 _cell_angle_alpha 90 _cell_angle_beta 95.684 _cell_angle_gamma 90 _cell_volume 960.890 _exptl_crystal_density_diffrn 2.822 _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 K 0.00000 0.08800 0.25000 0.94000 0.04900 Na 0.00000 0.08800 0.25000 0.03000 0.04900 AlM2 0.24950 0.08110 0.00200 0.83500 0.03330 MgM2 0.24950 0.08110 0.00200 0.02000 0.03330 FeM2 0.24950 0.08110 0.00200 0.17000 0.03330 SiT1 0.46430 0.92770 0.13360 0.62000 0.02500 AlT1 0.46430 0.92770 0.13360 0.38000 0.02500 SiT2 0.45010 0.26150 0.13500 1.00000 0.01500 O1 0.45160 0.09520 0.16760 1.00000 0.04600 O2 0.23170 0.82280 0.15860 1.00000 0.05400 O3 0.23260 0.35340 0.16880 1.00000 0.03900 O4 0.46440 0.94210 0.05370 1.00000 0.04300 O5 0.39430 0.25300 0.05460 1.00000 0.02900 O6 0.45730 0.56420 0.04850 0.94000 0.04700 F6 0.45730 0.56420 0.04850 0.06000 0.04700 H 0.36600 0.64640 0.06500 0.94000 ? 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 H 0.19000 0.05400 0.23000 0.01100 0.03000 0.04600