data_global _chemical_name_mineral 'Benitoite' loop_ _publ_author_name 'Hejny C' 'Miletich R' 'Jasser A' 'Schouwink P' 'Crichton W' 'Kahlenberg V' _journal_name_full 'American Mineralogist' _journal_volume 97 _journal_year 2012 _journal_page_first 1749 _journal_page_last 1763 _publ_section_title ; Second-order P6c2-P31c transition and structural crystallography of the cyclosilicate benitoite, BaTiSi3O9, at high pressure Note: P = 1.12 GPa ; _database_code_amcsd 0019507 _chemical_compound_source 'San Benito, California, USA' _chemical_formula_sum 'Ba Ti Si3 O9' _cell_length_a 6.6094 _cell_length_b 6.6094 _cell_length_c 9.7239 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 367.871 _exptl_crystal_density_diffrn 3.733 _symmetry_space_group_name_H-M 'P -6 c 2' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,x-y,-z' '-x+y,-x,1/2-z' '-y,-x,1/2+z' '-y,x-y,z' '-x+y,y,-z' 'x,y,1/2-z' 'x,x-y,1/2+z' '-x+y,-x,z' '-y,-x,-z' '-y,x-y,1/2-z' '-x+y,y,1/2+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Ba 0.66667 0.33333 0.00000 0.01640 Ti 0.33333 0.66667 0.00000 0.01140 Si 0.07070 0.78210 0.25000 0.00940 O1 0.81000 0.74600 0.25000 0.01000 O2 0.08610 0.65550 0.38780 0.01180