data_global _chemical_name_mineral 'Alumotantite' loop_ _publ_author_name 'Ercit T S' 'Hawthorne F C' 'Cerny P' _journal_name_full 'The Canadian Mineralogist' _journal_volume 30 _journal_year 1992 _journal_page_first 653 _journal_page_last 662 _publ_section_title ; The crystal structure of alumotantite: Its relation to the structures of simpsonite and the (Al,Ga)(Ta,Nb)O4 compounds ; _database_code_amcsd 0005280 _chemical_formula_sum 'Ta Al O4' _cell_length_a 4.473 _cell_length_b 11.308 _cell_length_c 4.775 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 241.523 _exptl_crystal_density_diffrn 7.478 _symmetry_space_group_name_H-M 'P b c n' 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,z' '1/2+x,1/2-y,-z' '1/2+x,1/2+y,1/2-z' '1/2-x,1/2-y,1/2+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 Ta 0.00000 0.16817 0.25000 ? Al 0.00000 0.43460 0.25000 0.00557 O1 0.22200 0.31200 0.08600 ? O2 0.26600 0.05800 0.07300 ? loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 Ta 0.00628 0.00259 0.00635 0.00000 -0.00022 0.00000 O1 0.00456 0.00842 0.00728 -0.00205 -0.00032 -0.00055 O2 0.01338 0.00130 0.01040 0.00000 -0.01060 0.00000