data_global _chemical_name_mineral 'Brassite' loop_ _publ_author_name 'Protas J' 'Gindt R' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 32 _journal_year 1976 _journal_page_first 1460 _journal_page_last 1466 _publ_section_title ; Structure cristalline de la brassite, MgHAsO4*4H2O, produit de deshydratation de la roesslerite ; _database_code_amcsd 0009557 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Mg As O8 H9' _cell_length_a 7.472 _cell_length_b 10.891 _cell_length_c 16.5850 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1349.647 _exptl_crystal_density_diffrn 2.326 _symmetry_space_group_name_H-M 'P b c a' loop_ _space_group_symop_operation_xyz 'x,y,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' '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 Mg 0.29410 0.47150 0.34680 As -0.00090 0.20670 0.09900 O1 0.41210 0.30300 -0.00650 O-H2 0.22190 0.16230 0.08770 O3 0.00170 0.34850 0.13710 O4 0.41210 0.10170 0.33890 Wat1 0.51500 0.10580 0.18690 Wat2 0.27760 0.42760 0.22560 Wat3 0.09540 0.34240 0.36970 Wat4 0.17500 0.01930 0.46690 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 Mg 0.01160 0.01412 0.01338 -0.00243 0.00239 -0.00018 As 0.00880 0.01184 0.01101 -0.00091 0.00213 0.00046 O1 0.02328 0.02614 0.00822 -0.00684 0.00239 0.00110 O-H2 0.01703 0.02884 0.02202 -0.00557 -0.00176 0.00293 O3 0.01604 0.01052 0.02620 0.00429 -0.00025 0.00128 O4 0.01824 0.01881 0.01491 -0.00107 -0.00100 -0.00055 Wat1 0.01547 0.01460 0.02202 0.00049 0.00207 -0.00119 Wat2 0.02537 0.02620 0.02271 -0.00033 -0.00634 -0.00018 Wat3 0.02034 0.02404 0.02536 -0.00115 0.00163 -0.00137 Wat4 0.02619 0.01761 0.02230 0.01121 -0.00502 0.00046