data_global _amcsd_formula_title 'KCuTa3O9' loop_ _publ_author_name 'Groult D' 'Hervieu M' 'Raveau B' _journal_name_full 'Journal of Solid State Chemistry' _journal_volume 53 _journal_year 1984 _journal_page_first 184 _journal_page_last 192 _publ_section_title ; A Pentagonal Tunnel Structure with Copper in Square Planar Coordination: The Oxides KCuNb3O9 and KCuTa3O9 _cod_database_code 1001197 ; _database_code_amcsd 0013527 _chemical_formula_sum 'K Cu Ta3 O9' _cell_length_a 8.862 _cell_length_b 10.187 _cell_length_c 7.638 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 689.537 _exptl_crystal_density_diffrn 7.605 _symmetry_space_group_name_H-M 'P n c 2' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-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 K1 0.08100 0.25900 0.25500 Cu1 0.50000 0.00000 0.25200 Cu2 0.50000 0.00000 0.75200 Ta1 0.42920 0.25200 -0.00300 Ta2 0.80210 0.43600 -0.01800 Ta3 0.79910 0.06130 -0.01200 O1 0.00000 0.00000 0.00000 O2 0.00000 0.00000 0.50000 O3 0.26000 0.11800 -0.03100 O4 0.25900 0.40300 0.06100 O5 0.57500 0.38400 0.05800 O6 0.57600 0.39200 0.46100 O7 0.87500 0.25300 0.00600 O8 0.40600 0.18600 0.25800 O9 0.17100 0.58900 0.24900 O10 0.27100 0.54000 0.75700