data_global _chemical_name_mineral 'Pigeonite' loop_ _publ_author_name 'Alvaro M' 'Nestola F' 'Ballaran T B' 'Camara F' 'Domeneghetti M C' 'Tazzoli V' _journal_name_full 'American Mineralogist' _journal_volume 95 _journal_year 2010 _journal_page_first 300 _journal_page_last 311 _publ_section_title ; High-pressure phase transition of a natural pigeonite Note: P = 3.587 GPa ; _database_code_amcsd 0005009 _chemical_compound_source 'Parana, Brazil' _chemical_formula_sum 'Fe1.008 Mg.871 Ca.121 (Si2 Al2) O6' _cell_length_a 9.518 _cell_length_b 8.804 _cell_length_c 5.056 _cell_angle_alpha 90 _cell_angle_beta 104.04 _cell_angle_gamma 90 _cell_volume 411.018 _exptl_crystal_density_diffrn 4.661 _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 FeA 0.00000 0.90630 0.25000 0.25300 0.00960 MgA 0.00000 0.90630 0.25000 0.74700 0.00960 FeB 0.00000 0.27750 0.25000 0.75500 0.01500 MgB 0.00000 0.27750 0.25000 0.12400 0.01500 CaB 0.00000 0.27750 0.25000 0.12100 0.01500 Si 0.29570 0.09050 0.22400 1.00000 0.00750 Al 0.29570 0.09050 0.22400 1.00000 0.00750 O1 0.12210 0.08950 0.14310 1.00000 0.01000 O2 0.37410 0.24000 0.35980 1.00000 0.01200 O3 0.35210 0.04850 0.94800 1.00000 0.01500