data_global _chemical_name_mineral 'Barberiite' loop_ _publ_author_name 'van Rensburg D J J' 'Boeyens J C A' _journal_name_full 'Journal of Solid State Chemistry' _journal_volume 5 _journal_year 1972 _journal_page_first 79 _journal_page_last 84 _publ_section_title ; The crystal structure of ammonium tetrafluoroborate IV at 140 K Sample: T = 140 K Note: x(H2), y(H2) adjusted to match reported bond lengths ; _database_code_amcsd 0013299 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'N H4 B F4' _cell_length_a 7.243 _cell_length_b 8.808 _cell_length_c 5.908 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 376.909 _exptl_crystal_density_diffrn 1.848 _symmetry_space_group_name_H-M 'P b n m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,1/2-z' '-x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '1/2-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-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 N 0.17140 0.18430 0.25000 0.00892 H1 0.13000 0.29000 0.25000 0.03800 H2 0.28900 0.19800 0.25000 0.03800 H3 0.10000 0.15000 0.08000 0.03800 B 0.69050 0.07220 0.25000 0.01549 F1 0.58220 0.94030 0.25000 0.03047 F2 0.57640 0.20190 0.25000 0.01990 F3 0.80600 0.07680 0.05270 0.01861