data_global _chemical_name_mineral 'Aegirine' loop_ _publ_author_name 'McCarthy A C' 'Downs R T' 'Thompson R M' 'Redhammer G J' _journal_name_full 'American Mineralogist' _journal_volume 93 _journal_year 2008 _journal_page_first 1829 _journal_page_last 1837 _publ_section_title ; In situ high-pressure single-crystal X-ray study of aegirine, NaFe3+Si2O6, and the role of M1 size in clinopyroxene compressibility Note: Pressure = 0.0001 GPa ; _database_code_amcsd 0004759 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Na Fe Si2 O6' _cell_length_a 9.6539 _cell_length_b 8.7928 _cell_length_c 5.2935 _cell_angle_alpha 90 _cell_angle_beta 107.436 _cell_angle_gamma 90 _cell_volume 428.692 _exptl_crystal_density_diffrn 3.579 _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_U_iso_or_equiv NaM2 0.00000 0.29920 0.25000 0.01294 FeM1 0.00000 0.89878 0.25000 0.00515 Si 0.29072 0.08945 0.23561 0.00469 O1 0.11430 0.07860 0.13760 0.00643 O2 0.35880 0.25580 0.30070 0.00854 O3 0.35200 0.00780 0.01200 0.00741 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 NaM2 0.01564 0.01077 0.00923 0.00000 -0.00118 0.00000 FeM1 0.00511 0.00501 0.00522 0.00000 0.00134 0.00000 Si 0.00456 0.00517 0.00444 -0.00049 0.00156 -0.00018 O1 0.00533 0.00732 0.00656 -0.00074 0.00163 -0.00018 O2 0.01023 0.00666 0.00933 -0.00242 0.00386 -0.00139 O3 0.00623 0.00944 0.00659 0.00004 0.00191 -0.00173