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 = 3.167 GPa ; _database_code_amcsd 0005007 _chemical_compound_source 'Parana, Brazil' _chemical_formula_sum 'Fe1.008 Mg.871 Ca.121 (Si1.98 Al.02) O6' _cell_length_a 9.621 _cell_length_b 8.827 _cell_length_c 5.199 _cell_angle_alpha 90 _cell_angle_beta 107.82 _cell_angle_gamma 90 _cell_volume 420.340 _exptl_crystal_density_diffrn 3.705 _symmetry_space_group_name_H-M 'P 1 21/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-x,1/2+y,1/2-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 FeA 0.25090 0.65650 0.22860 0.25300 0.01030 MgA 0.25090 0.65650 0.22860 0.74700 0.01030 FeB 0.25730 0.02190 0.22450 0.75500 0.01200 MgB 0.25730 0.02190 0.22450 0.12400 0.01200 CaB 0.23800 0.03300 0.25600 0.12100 0.03000 SiA 0.04120 0.34170 0.27320 0.99000 0.00990 AlA 0.04120 0.34170 0.27320 0.01000 0.00990 SiB 0.54990 0.83780 0.23320 0.99000 0.00710 AlB 0.54990 0.83780 0.23320 0.01000 0.00710 O1A 0.86760 0.34000 0.17100 1.00000 0.01000 O1B 0.37420 0.83730 0.13100 1.00000 0.00900 O2A 0.12000 0.50350 0.33000 1.00000 0.00900 O2B 0.62590 0.98760 0.37000 1.00000 0.01500 O3A 0.10400 0.26230 0.57300 1.00000 0.02200 O3B 0.60700 0.70590 0.47000 1.00000 0.01500