data_global _amcsd_formula_title 'O18 Rb2 Ta6 Ti' loop_ _publ_author_name 'Desgardin G' 'Robert C' 'Groult D' 'Raveau B' _journal_name_full 'Journal of Solid State Chemistry' _journal_volume 22 _journal_year 1977 _journal_page_first 101 _journal_page_last 111 _publ_section_title ; Une nouvelle famille structurale: les titanoniobates et titanotantalates A2 Nb6 Ti O18 et A2 Ta6 Ti O18 _cod_database_code 1001014 ; _database_code_amcsd 0013348 _chemical_formula_sum 'Rb2 (Ta5.999 Ti1.001) O18' _cell_length_a 7.512 _cell_length_b 7.512 _cell_length_c 8.231 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 402.248 _exptl_crystal_density_diffrn 6.573 _symmetry_space_group_name_H-M 'P -3 m 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '-y,-x,z' 'y,-x+y,-z' '-x,-x+y,-z' '-x+y,-x,z' '-x+y,y,z' '-x,-y,-z' 'y,x,-z' '-y,x-y,z' 'x,x-y,z' 'x-y,x,-z' 'x-y,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy Rb1 0.33333 0.66667 0.65000 1.00000 Ta1 0.00000 0.00000 0.50000 0.85700 Ti1 0.00000 0.00000 0.50000 0.14300 Ta2 0.17020 -0.17020 0.14810 0.85700 Ti2 0.17020 -0.17020 0.14810 0.14300 O1 0.44700 -0.44700 0.16667 1.00000 O2 0.86000 -0.86000 0.11000 1.00000 O3 0.13000 -0.13000 0.35300 1.00000