data_global _chemical_name_mineral 'Bismutocolumbite' loop_ _publ_author_name 'Zubkova N V' 'Pushcharovsky D Y' 'Giester G' 'Smolin A S' 'Tillmanns E' 'Brandstatter F' 'Hammer V' 'Peretyazhko I S' 'Sapozhnikov A N' 'Kashaev A A' _journal_name_full 'Neues Jahrbuch fur Mineralogie, Monatshefte' _journal_volume 2002 _journal_year 2002 _journal_page_first 145 _journal_page_last 159 _publ_section_title ; Bismutocolumbite, Bi(Nb.79Ta.21)O4, stibiocolumbite, Sb(Nb.67Ta.33)O4 and their structural relation to the other ABO4 minerals with stibiotantalite (SbTaO4) structure ; _database_code_amcsd 0014918 _chemical_compound_source 'Malkhan field, Central Transbaikalia, Russia' _chemical_formula_sum 'Bi (Nb.79 Ta.21) O4' _cell_length_a 5.668 _cell_length_b 11.725 _cell_length_c 4.971 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 330.359 _exptl_crystal_density_diffrn 7.728 _symmetry_space_group_name_H-M 'P n n a' loop_ _space_group_symop_operation_xyz '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' '1/2+x,y,-z' '1/2-x,-y,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 Bi 0.25000 0.50000 0.78030 1.00000 0.01840 Nb 0.34880 0.25000 0.25000 0.79000 0.00800 Ta 0.34880 0.25000 0.25000 0.21000 0.00800 O1 0.13920 0.30510 0.50460 1.00000 0.01310 O2 0.41430 0.09790 0.41240 1.00000 0.00920