data_global _chemical_name_mineral 'Huntite' loop_ _publ_author_name 'Dollase W A' 'Reeder R J' _journal_name_full 'American Mineralogist' _journal_volume 71 _journal_year 1986 _journal_page_first 163 _journal_page_last 166 _publ_section_title ; Crystal structure refinement of huntite, CaMg3(CO3)4, with X-ray powder data ; _database_code_amcsd 0001006 _chemical_formula_sum 'Ca Mg3 C4 O12' _cell_length_a 9.5027 _cell_length_b 9.5027 _cell_length_c 7.8212 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 611.643 _exptl_crystal_density_diffrn 2.875 _symmetry_space_group_name_H-M 'R 3 2' loop_ _space_group_symop_operation_xyz 'x,y,z' '2/3+x,1/3+y,1/3+z' '1/3+x,2/3+y,2/3+z' '-x,-x+y,-z' '2/3-x,1/3-x+y,1/3-z' '1/3-x,2/3-x+y,2/3-z' 'y,x,-z' '2/3+y,1/3+x,1/3-z' '1/3+y,2/3+x,2/3-z' 'x-y,-y,-z' '2/3+x-y,1/3-y,1/3-z' '1/3+x-y,2/3-y,2/3-z' '-y,x-y,z' '2/3-y,1/3+x-y,1/3+z' '1/3-y,2/3+x-y,2/3+z' '-x+y,-x,z' '2/3-x+y,1/3-x,1/3+z' '1/3-x+y,2/3-x,2/3+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Ca 0.00000 0.00000 0.00000 0.01191 Mg 0.54430 0.00000 0.00000 0.01191 C1 0.00000 0.00000 0.50000 0.01191 C2 0.45350 0.00000 0.50000 0.01191 O1 0.86630 0.00000 0.50000 0.01191 O2 0.58950 0.00000 0.50000 0.01191 O3 0.45690 0.13550 0.51610 0.01191