data_global _chemical_name_mineral 'Rollandite' loop_ _publ_author_name 'Sarp H' 'Cerny R' _journal_name_full 'European Journal of Mineralogy' _journal_volume 12 _journal_year 2000 _journal_page_first 1045 _journal_page_last 1050 _publ_section_title ; Rollandite, Cu3(AsO4)2.4H2O, a new mineral: its description and crystal structure ; _database_code_amcsd 0006846 _chemical_formula_sum 'Cu3 As2 O12 H8' _cell_length_a 5.6906 _cell_length_b 17.061 _cell_length_c 9.732 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 944.854 _exptl_crystal_density_diffrn 3.800 _symmetry_space_group_name_H-M 'P n m a' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,z' '-x,1/2+y,-z' '1/2-x,1/2+y,1/2+z' '1/2+x,1/2-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_U_iso_or_equiv Cu1 0.42640 0.51379 0.35100 0.00990 Cu2 0.02300 0.25000 0.22140 0.00720 As 0.36490 0.10323 0.10043 0.00610 O1 0.01900 0.14630 0.52310 0.01300 O2 0.02400 0.03510 0.31880 0.00900 O3 0.11600 0.06110 0.03650 0.01000 Wat4 0.27500 0.59620 0.23860 0.01100 O5 0.28000 0.17450 0.21500 0.00800 Wat6 0.21400 0.25000 0.82300 0.02500 Wat7 0.36000 0.25000 0.48470 0.01100