data_9000327 _chemical_name 'Aegirine' loop_ _publ_author_name 'Cameron M' 'Sueno S' 'Prewitt C T' 'Papike J J' _journal_name_full "American Mineralogist" _journal_volume 58 _journal_year 1973 _journal_page_first 594 _journal_page_last 618 _publ_section_title ; High-temperature crystal chemistry of acmite, diopside, hedenbergite, jadeite, spodumene, and ureyite T = 24 C pyroxene ; _chemical_formula_sum 'Si2 Fe Na O6' _cell_length_a 9.658 _cell_length_b 8.795 _cell_length_c 5.294 _cell_angle_alpha 90 _cell_angle_beta 107.42 _cell_angle_gamma 90 _cell_volume 429.059 _symmetry_space_group_name_H-M 'C 1 2/c 1' loop_ _symmetry_equiv_pos_as_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 Si 0.29050 0.08940 0.23510 Fe1 0.00000 0.89890 0.25000 Na2 0.00000 0.29990 0.25000 O1 0.11410 0.07840 0.13800 O2 0.35820 0.25580 0.30010 O3 0.35180 0.00790 0.01180