data_global _chemical_name_mineral 'Effenbergerite' loop_ _publ_author_name 'Janczak J' 'Kubiak R' _journal_name_full 'Acta Crystallographica, Section C' _journal_volume 48 _journal_year 1992 _journal_page_first 1299 _journal_page_last 1301 _publ_section_title ; Refinement of the structure of barium copper silicate BaCu[Si4O10] at 300 K ; _database_code_amcsd 0018736 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Ba Cu Si4 O10' _cell_length_a 7.447 _cell_length_b 7.447 _cell_length_c 16.138 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 894.978 _exptl_crystal_density_diffrn 3.512 _symmetry_space_group_name_H-M 'P 4/n c c' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2-y,1/2-x,1/2+z' 'y,x,1/2-z' 'y,-x,-z' '1/2-y,1/2+x,z' 'x,-y,1/2+z' '1/2-x,1/2+y,1/2-z' '1/2+x,1/2+y,-z' '-x,-y,z' '1/2+y,1/2+x,1/2+z' '-y,-x,1/2-z' '-y,x,-z' '1/2+y,1/2-x,z' '-x,y,1/2+z' '1/2+x,1/2-y,1/2-z' '1/2-x,1/2-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Ba 0.00000 0.00000 0.00000 0.01000 Cu 0.00000 0.50000 0.09440 0.00770 Si 0.26810 0.18870 0.15460 0.00730 O1 0.22610 0.22610 0.25000 0.03100 O2 0.47360 0.24840 0.13660 0.01600 O3 0.13670 0.28180 0.09800 0.01570