data_global _chemical_name_mineral 'Barylite' loop_ _publ_author_name 'Rastsvetaeva R K' 'Chukanov N V' _journal_name_full 'Doklady Akademii Nauk' _journal_volume 388 _journal_year 2003 _journal_page_first 205 _journal_page_last 207 _publ_section_title ; Crystal structure and microtwinning of a new mineral clinobarylite, BaBe2Si2O7 Note: polytype barylite-1O ; _database_code_amcsd 0019239 _chemical_formula_sum 'Ba Be2 Si2 O7' _cell_length_a 11.618 _cell_length_b 4.904 _cell_length_c 4.655 _cell_angle_alpha 89.94 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 265.217 _exptl_crystal_density_diffrn 4.051 _symmetry_space_group_name_H-M 'P m 1 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '-x,y,z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Ba1 0.00000 0.46490 0.00000 0.01874 Ba2 0.50000 0.05880 0.49940 0.01545 Be1 0.24900 0.08600 0.01400 0.01013 Be2 0.25000 0.41900 0.51900 0.01900 Si1 0.37130 0.58660 0.02440 0.01153 Si2 0.12770 0.93610 0.52070 0.01330 O1 0.36310 0.90300 -0.04600 0.00887 O2 0.50000 0.48700 0.08600 0.01583 O3 0.00000 0.04500 0.57900 0.02280 O4 0.13980 0.60900 0.45300 0.01520 O5 0.22340 0.12600 0.36000 0.00760 O6 0.13360 -0.00500 -0.13600 0.01140 O7 0.27720 0.39700 -0.14100 0.01900 O8 0.36840 0.53300 0.36300 0.01646