data_global _chemical_name_mineral 'Melanothallite' loop_ _publ_author_name 'Krivovichev S V' 'Filatov S K' 'Burns P C' _journal_name_full 'The Canadian Mineralogist' _journal_volume 40 _journal_year 2002 _journal_page_first 1185 _journal_page_last 1190 _publ_section_title ; The cuprite-like framework of OCu4 tetrahedra in the crystal structure of synthetic melanothallite, Cu2OCl2, and its negative thermal expansion ; _database_code_amcsd 0005787 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Cu2 Cl2 O' _cell_length_a 7.4691 _cell_length_b 9.5969 _cell_length_c 9.700 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 695.298 _exptl_crystal_density_diffrn 4.089 _symmetry_space_group_name_H-M 'F d d d' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2+y,1/2+z' '1/2+x,y,1/2+z' '1/2+x,1/2+y,z' '3/4+x,-y,3/4+z' '3/4+x,1/2-y,1/4+z' '1/4+x,-y,1/4+z' '1/4+x,1/2-y,3/4+z' '3/4-x,y,3/4-z' '3/4-x,1/2+y,1/4-z' '1/4-x,y,1/4-z' '1/4-x,1/2+y,3/4-z' '-x,3/4+y,3/4+z' '-x,1/4+y,1/4+z' '1/2-x,3/4+y,1/4+z' '1/2-x,1/4+y,3/4+z' 'x,3/4-y,3/4-z' 'x,1/4-y,1/4-z' '1/2+x,3/4-y,1/4-z' '1/2+x,1/4-y,3/4-z' '3/4+x,3/4+y,-z' '3/4+x,1/4+y,1/2-z' '1/4+x,3/4+y,1/2-z' '1/4+x,1/4+y,-z' '3/4-x,3/4-y,z' '3/4-x,1/4-y,1/2+z' '1/4-x,3/4-y,1/2+z' '1/4-x,1/4-y,z' '-x,-y,-z' '-x,1/2-y,1/2-z' '1/2-x,-y,1/2-z' '1/2-x,1/2-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Cu 0.00000 0.00000 0.50000 0.01400 Cl 0.12500 0.12500 0.32431 0.02130 O 0.12500 0.12500 0.62500 0.01270 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 Cu 0.01790 0.01300 0.01100 -0.00260 -0.00080 -0.00060 Cl 0.02890 0.02200 0.01310 -0.00870 0.00000 0.00000 O 0.01670 0.01190 0.00940 0.00000 0.00000 0.00000