data_global
_chemical_name_mineral 'Dymkovite'
loop_
_publ_author_name
'Pekov I V'
'Levitskiy V V'
'Krivovichev S V'
'Zolotarev A A'
'Chukanov N V'
'Bryzgalov I A'
'Zadov A E'
_journal_name_full 'European Journal of Mineralogy'
_journal_volume 24 
_journal_year 2012
_journal_page_first 923
_journal_page_last 930
_publ_section_title
;
 New nickel-uranium-arsenic mineral species from the oxidation zone of
 the Belorechenskoye deposit, Northern Caucasus, Russia: II.
 Dymkovite, Ni(UO2)2(As3+O3)2*7H2O, a seelite-related arsenite
;
_database_code_amcsd 0019395
_chemical_compound_source 'Belorechenskoye deposit, Northern Caucasus, Russia'
_chemical_formula_sum 'U2 As2 (Ni.6 Mg.4) O17 H14'
_cell_length_a 17.91
_cell_length_b 6.985
_cell_length_c 6.594
_cell_angle_alpha 90
_cell_angle_beta 99.89
_cell_angle_gamma 90
_cell_volume 812.659
_exptl_crystal_density_diffrn      3.911
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-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_occupancy
_atom_site_U_iso_or_equiv
U   0.24091   0.00000   0.12781   1.00000   0.03380
As   0.20792   0.50000   0.32550   1.00000   0.04250
Ni   0.00000   0.00000   0.50000   0.60000   0.04900
Mg   0.00000   0.00000   0.50000   0.40000   0.04900
O1   0.34150   0.00000   0.21200   1.00000   0.05100
O2   0.14150   0.00000   0.04400   1.00000   0.04700
O3   0.22250   0.00000   0.45960   1.00000   0.04300
O4   0.24070   0.67380   0.17900   1.00000   0.05000
Wat1   0.09060   0.18100   0.52100   0.50000   0.06600
Wat2  -0.02180   0.13900   0.74300   0.50000   0.10400
Wat3   0.06000   0.19800   0.69200   0.50000   0.16000
Wat4   0.00000   0.50000   0.18500   0.50000   0.13200
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
U 0.05460 0.01700 0.03260 0.00000 0.01570 0.00000
As 0.05790 0.03820 0.03470 0.00000 0.01740 0.00000
Ni 0.03900 0.04600 0.06400 0.00000 0.01100 0.00000
Mg 0.03900 0.04600 0.06400 0.00000 0.01100 0.00000
O1 0.03900 0.04600 0.06400 0.00000 0.01100 0.00000
O2 0.05200 0.04800 0.05200 0.00000 0.01000 0.00000
O3 0.05300 0.03500 0.05500 0.00000 0.01100 0.00000
O4 0.05000 0.04100 0.03800 0.00000 0.01000 0.00000