data_global _chemical_name_mineral 'Burkeite' loop_ _publ_author_name 'Giuseppetti G' 'Mazzi F' 'Tadini C' _journal_name_full 'Neues Jahrbuch fur Mineralogie, Monatshefte' _journal_volume 1988 _journal_year 1988 _journal_page_first 203 _journal_page_last 221 _publ_section_title ; The crystal structure of synthetic burkeite Na4SO4(CO3)t(SO4)1-t Sample A Note sign of y-coordinate for O3 and O5 altered to reproduce reported bond lengths ; _database_code_amcsd 0014823 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Na4 C.61 S1.39 O7.39' _cell_length_a 5.170 _cell_length_b 9.217 _cell_length_c 7.058 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 336.327 _exptl_crystal_density_diffrn 2.588 _symmetry_space_group_name_H-M 'P m n m' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2-x,y,z' '1/2+x,-y,-z' 'x,y,1/2-z' '-x,-y,1/2+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 Na1 0.25000 0.75090 0.00510 1.00000 0.02837 Na2 0.25000 0.42540 0.25000 1.00000 0.06915 Na3 0.75000 0.87540 0.25000 1.00000 0.02774 CT1 0.75000 0.55840 0.25000 0.61000 0.02039 ST1 0.75000 0.55840 0.25000 0.39000 0.02039 ST2 0.29510 0.09130 0.25000 0.50000 0.01469 O1 0.75000 0.42260 0.25000 0.85000 0.04813 O2 0.53570 0.64030 0.25000 0.88000 0.03673 O3 0.75000 -0.46930 0.08190 0.15000 0.06966 O4 0.93070 0.58090 0.09510 0.12000 0.07599 O5 0.19270 -0.16450 0.08150 0.50000 0.03166 O6 0.21640 -0.06320 0.25000 0.50000 0.01900 O7 0.57980 0.10570 0.25000 0.50000 0.02786