data_global
_chemical_name_mineral 'Davidlloydite'
loop_
_publ_author_name
'Hawthorne F C'
'Cooper M A'
'Abdu Y A'
'Ball N A'
'Back M E'
'Tait K T'
_journal_name_full 'Mineralogical Magazine'
_journal_volume 76 
_journal_year 2012
_journal_page_first 45
_journal_page_last 57
_publ_section_title
;
 Davidlloydite, ideally Zn3(AsO4)2(H2O)4, a new arsenate mineral
 from the Tsumeb mine, Otjikoto (Oshikoto) region, Namibia:
 description and crystal structure
;
_database_code_amcsd 0018665
_chemical_compound_source 'Tsumeb, Namibia'
_chemical_formula_sum 'Zn2.6 Cu.4 As2 O12 H8'
_cell_length_a 5.9756
_cell_length_b 7.6002
_cell_length_c 5.4471
_cell_angle_alpha 84.2892
_cell_angle_beta 90.4920
_cell_angle_gamma 87.9958
_cell_volume 245.988
_exptl_crystal_density_diffrn      3.681
_symmetry_space_group_name_H-M 'P -1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
Zn1   0.00000   0.50000   0.50000   0.60000   0.01224
Cu1   0.00000   0.50000   0.50000   0.40000   0.01224
Zn2   0.23922   0.10407   0.81081   1.00000   0.01226
As   0.25896   0.87032   0.33696   1.00000   0.00916
O1   0.48130   0.76440   0.22590   1.00000   0.01530
O2   0.29960   0.89720   0.63540   1.00000   0.01460
O3   0.02710   0.74640   0.31440   1.00000   0.01280
O4   0.19520   0.06300   0.16740   1.00000   0.01450
O5   0.22290   0.40100   0.27260   1.00000   0.01810
O6   0.27110   0.54200   0.78340   1.00000   0.02080
H1   0.21100   0.27620   0.24500   1.00000   0.03900
H2   0.23200   0.45300   0.10100   1.00000   0.05600
H3   0.41300   0.48100   0.74800   1.00000   0.05800
H4   0.32500   0.66200   0.79100   1.00000   0.05900
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
Zn1 0.01425 0.01053 0.01178 0.00005 0.00126 -0.00034
Cu1 0.01425 0.01053 0.01178 0.00005 0.00126 -0.00034
Zn2 0.01204 0.01445 0.01032 0.00121 -0.00006 -0.00186
As 0.00945 0.00940 0.00869 0.00002 0.00025 -0.00125
O1 0.01190 0.01400 0.02040 0.00070 0.00370 -0.00450
O2 0.02000 0.01440 0.00960 0.00070 -0.00110 -0.00270
O3 0.01030 0.01200 0.01570 -0.00140 -0.00120 0.00020
O4 0.02090 0.01160 0.01050 0.00150 -0.00060 0.00100
O5 0.02530 0.01340 0.01550 0.00090 0.00370 -0.00070
O6 0.01900 0.01620 0.02700 -0.00090 0.00310 -0.00080