data_global _chemical_name_mineral 'Wesselsite' loop_ _publ_author_name 'Knight K S' 'Henderson C M B' 'Clark S M' _journal_name_full 'European Journal of Mineralogy' _journal_volume 22 _journal_year 2010 _journal_page_first 411 _journal_page_last 423 _publ_section_title ; Structural variations in the wesselsite-effenbergerite (Sr1-xBaxCuSi4O10) solid solution Sample: x = .193 ; _database_code_amcsd 0018769 _chemical_compound_source 'Synthetic' _chemical_formula_sum '(Ba.193 Sr.807) Cu Si4 O10' _cell_length_a 7.3752 _cell_length_b 7.3752 _cell_length_c 15.6902 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 853.446 _exptl_crystal_density_diffrn 3.371 _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' '1/2+y,1/2+x,1/2-z' '1/2+y,-x,-z' '1/2-y,x,z' 'x,1/2-y,1/2+z' '-x,1/2+y,1/2-z' '1/2+x,1/2+y,-z' '1/2-x,1/2-y,z' 'y,x,1/2+z' '-y,-x,1/2-z' '-y,1/2+x,-z' 'y,1/2-x,z' '1/2-x,y,1/2+z' '1/2+x,-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_occupancy _atom_site_U_iso_or_equiv Ba 0.25000 0.75000 0.00000 0.19300 0.06600 Sr 0.25000 0.75000 0.00000 0.80700 0.06600 Cu 0.25000 0.25000 0.09060 1.00000 0.09100 Si 0.50930 0.93170 0.15110 1.00000 0.02800 O1 0.45110 0.98500 0.24600 0.50000 0.06300 O2 0.71640 0.00110 0.13240 1.00000 0.07600 O3 0.37030 0.02130 0.08730 1.00000 0.08100