data_global
_chemical_name_mineral 'Lammerite'
loop_
_publ_author_name
'Hawthorne F C'
_journal_name_full 'American Mineralogist'
_journal_volume 71 
_journal_year 1986
_journal_page_first 206
_journal_page_last 209
_publ_section_title
;
 Lammerite, Cu3(AsO4)2, a modulated close-packed structure
;
_database_code_amcsd 0001009
_chemical_formula_sum 'Cu3 As2 O8'
_cell_length_a 5.079
_cell_length_b 11.611
_cell_length_c 5.394
_cell_angle_alpha 90
_cell_angle_beta 111.72
_cell_angle_gamma 90
_cell_volume 295.513
_exptl_crystal_density_diffrn      5.265
_symmetry_space_group_name_H-M 'P 1 21/a 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2-y,z'
  '1/2-x,1/2+y,-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   0.00000   0.50000   0.50000   0.01250
Cu2   0.24620   0.83670   0.85630   0.01480
As  -0.11110   0.88510   0.26250   0.00960
O1   0.19210   0.91730   0.22030   0.01300
O2  -0.09460   0.81570   0.53900   0.01500
O3   0.17170   0.68710   0.99040   0.01300
O4   0.28930   0.99020   0.73320   0.01200