data_global _chemical_name_mineral 'Aragonite' loop_ _publ_author_name 'Ye Y' 'Smyth J R' 'Boni P' _journal_name_full 'American Mineralogist' _journal_volume 97 _journal_year 2012 _journal_page_first 707 _journal_page_last 712 _publ_section_title ; Crystal structure and thermal expansion of aragonite-group carbonates by single-crystal X-ray diffraction Note: T = 224 K ; _database_code_amcsd 0018849 _chemical_compound_source 'natural, unknown locality' _chemical_formula_sum '(Ca.997 Sr.003) C O3' _cell_length_a 4.9564 _cell_length_b 7.9536 _cell_length_c 5.7253 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 225.698 _exptl_crystal_density_diffrn 2.950 _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 _atom_site_occupancy _atom_site_U_iso_or_equiv Ca 0.25000 0.41510 0.76000 0.99700 0.01400 Sr 0.25000 0.41510 0.76000 0.00300 0.01400 C 0.25000 0.76360 -0.08700 1.00000 0.01600 O1 0.25000 0.92440 -0.09530 1.00000 0.01500 O2 0.47480 0.68020 -0.08700 1.00000 0.01500 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 0.01800 0.01600 0.00900 0.00000 0.00000 0.00040 Sr 0.01800 0.01600 0.00900 0.00000 0.00000 0.00040 C 0.02400 0.02400 0.00000 0.00000 0.00000 -0.00500 O1 0.02500 0.00800 0.01000 0.00000 0.00000 -0.00400 O2 0.01900 0.01400 0.01300 0.00700 0.00100 0.00100