data_global _chemical_name_mineral 'Aegirine' loop_ _publ_author_name 'Redhammer G J' 'Amthauer G' 'Roth G' 'Tippelt G' 'Lottermoser W' _journal_name_full 'American Mineralogist' _journal_volume 91 _journal_year 2006 _journal_page_first 1271 _journal_page_last 1292 _publ_section_title ; Single crystal X-ray diffraction and temperature dependent 57Fe Mossbauer spectroscopy on the hedenbergite - aegirine (Ca,Na)(Fe2+,Fe3+)Si2O6 solid solution Sample: Ae751, T = 298 K ; _database_code_amcsd 0004210 _chemical_compound_source 'Synthetic' _chemical_formula_sum '(Na.751 Ca.249) Fe Si2 O6' _cell_length_a 9.6953 _cell_length_b 8.8491 _cell_length_c 5.2856 _cell_angle_alpha 90 _cell_angle_beta 106.778 _cell_angle_gamma 90 _cell_volume 434.172 _exptl_crystal_density_diffrn 3.599 _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 Na2 0.00000 0.30050 0.25000 0.75100 0.01040 Ca2 0.00000 0.30050 0.25000 0.24900 0.01040 Fe3+1 0.00000 0.90060 0.25000 0.75100 0.00530 Fe2+1 0.00000 0.90060 0.25000 0.24900 0.00530 Si 0.28970 0.09050 0.23360 1.00000 0.00180 O1 0.11470 0.08040 0.14000 1.00000 0.00470 O2 0.35900 0.25440 0.30630 1.00000 0.00720 O3 0.35140 0.01210 0.00740 1.00000 0.00560