data_global _chemical_name_mineral 'Ilvaite' loop_ _publ_author_name 'Bonazzi P' 'Bindi L' _journal_name_full 'American Mineralogist' _journal_volume 87 _journal_year 2002 _journal_page_first 845 _journal_page_last 852 _publ_section_title ; Structural properties and heat-induced oxidation-dehydrogenation of manganoan ilvaite from perda Niedda mine, Sardinia, Italy Sample: PN6-690, Crystal at room temperature, annealed at 690 C for 48 hrs ; _database_code_amcsd 0002854 _chemical_formula_sum 'Ca.98 Mn.74 Fe2.28 Si2 O9' _cell_length_a 13.015 _cell_length_b 8.873 _cell_length_c 5.816 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 671.644 _exptl_crystal_density_diffrn 4.029 _symmetry_space_group_name_H-M 'P n a m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,1/2-z' '-x,-y,1/2+z' '1/2-x,1/2+y,1/2+z' '1/2+x,1/2-y,1/2-z' '1/2+x,1/2-y,z' '1/2-x,1/2+y,-z' '-x,-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 CaA 0.81955 0.37599 0.75000 0.98000 0.01320 MnA 0.81955 0.37599 0.75000 0.02000 0.01320 FeM1 0.88830 0.05682 -0.00600 1.00000 0.00940 MnM2 0.92869 0.73676 0.25000 0.72000 0.01110 FeM2 0.92869 0.73676 0.25000 0.28000 0.01110 Si1 0.96660 0.36380 0.25000 1.00000 0.00950 Si2 0.68690 0.23490 0.25000 1.00000 0.00730 O1 0.01620 0.01980 0.75000 1.00000 0.01370 O2 0.94390 0.26830 0.01430 1.00000 0.01250 O3 0.78500 0.11440 0.25000 1.00000 0.01200 O4 0.67610 0.33580 0.01590 1.00000 0.01350 O5 0.59220 0.10910 0.25000 1.00000 0.01280 O6 0.59280 0.01810 0.75000 1.00000 0.02190 O7 0.80950 0.11510 0.75000 1.00000 0.01140