data_global _chemical_name_mineral 'Lecontite' loop_ _publ_author_name 'Arzt S' 'Glazer A M' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 50 _journal_year 1994 _journal_page_first 425 _journal_page_last 431 _publ_section_title ; The optical activity and absolute optical chirality of NaNH4SO4*2H2O ; _database_code_amcsd 0009882 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'N H8 Na S O6' _cell_length_a 6.253 _cell_length_b 8.228 _cell_length_c 12.856 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 661.437 _exptl_crystal_density_diffrn 1.738 _symmetry_space_group_name_H-M 'P 21 21 21' loop_ _space_group_symop_operation_xyz 'x,y,z' '-x,1/2+y,1/2-z' '1/2+x,1/2-y,-z' '1/2-x,-y,1/2+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv N 0.36960 0.17290 0.85530 0.03800 H5 0.85000 0.38000 0.18900 0.10000 H6 0.78000 0.32900 0.10100 0.10000 H7 0.94000 0.24000 0.13600 0.10000 H8 0.75000 0.26000 0.17100 0.10000 Na 0.91120 0.26520 0.48480 0.02800 S 0.37290 0.08410 0.12830 0.02370 O1 0.18840 0.06740 0.19900 0.04300 O2 0.57320 0.06520 0.18820 0.04600 O3 0.36740 0.24530 0.08050 0.04900 O4 0.13990 0.04020 0.54680 0.03000 O5 0.68960 0.21180 0.63520 0.03400 O6 0.65900 0.07910 0.40400 0.03500 H1 0.78900 0.88900 0.16000 0.04500 H2 0.85000 0.72900 0.17200 0.04500 H3 0.39200 0.60000 0.14200 0.04500 H4 0.38000 0.48600 0.08000 0.04500 loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 N 0.04000 0.04400 0.03100 0.00200 -0.00200 -0.00300 Na 0.02290 0.03100 0.02900 0.00250 0.00200 -0.00030 S 0.02970 0.01990 0.02150 0.00080 0.00070 -0.00310 O1 0.04200 0.05000 0.03700 -0.00500 0.01400 -0.00500 O2 0.04100 0.05100 0.03800 0.00600 -0.01600 -0.01800 O3 0.08100 0.02100 0.04200 0.00000 0.00000 0.00100 O4 0.03500 0.02600 0.03100 -0.00100 0.00900 0.01200 O5 0.03800 0.03500 0.02800 0.00300 -0.00300 -0.00400 O6 0.05500 0.02400 0.03100 -0.00200 -0.01000 0.00100