data_global _chemical_name_mineral 'Aragonite' loop_ _publ_author_name 'Dal Negro A' 'Ungaretti L' _journal_name_full 'American Mineralogist' _journal_volume 56 _journal_year 1971 _journal_page_first 768 _journal_page_last 772 _publ_section_title ; Refinement of the crystal structure of aragonite ; _database_code_amcsd 0000236 _chemical_compound_source 'Vertaizon-Alvernia, France' _chemical_formula_sum 'Ca C O3' _cell_length_a 4.9616 _cell_length_b 7.9705 _cell_length_c 5.7394 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 226.973 _exptl_crystal_density_diffrn 2.929 _symmetry_space_group_name_H-M 'P m c n' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2-x,y,z' '1/2+x,-y,-z' '1/2+x,1/2+y,1/2-z' '1/2-x,1/2-y,1/2+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 Ca 0.25000 0.41510 0.24030 C 0.25000 0.76270 0.08500 O1 0.25000 0.92310 0.09520 O2 0.47290 0.68010 0.08700 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 Ca 0.00828 0.00913 0.00796 0.00000 0.00000 -0.00035 C 0.01061 0.01141 0.00846 0.00000 0.00000 0.00138 O1 0.01850 0.01243 0.01647 0.00000 0.00000 0.00250 O2 0.01062 0.01778 0.01700 0.00247 0.00099 -0.00060