data_9005272
_chemical_name 'Annabergite'
loop_
_publ_author_name
'Wildner M'
'Giester G'
'Lengauer C L'
'McCammon C A'
_journal_name_full "European Journal of Mineralogy"
_journal_volume 8
_journal_year 1996
_journal_page_first 187
_journal_page_last 192
_publ_section_title
;
 Structure and crystal chemistry of vivianite-type compounds: Crystal
 structures of erythrite and annabergite with a Mossbauer study of erythrite
;
_chemical_formula_sum '(Ni2.64 Mg.36) As2 O16 H16'
_cell_length_a 10.179
_cell_length_b 13.309
_cell_length_c 4.725
_cell_angle_alpha 90
_cell_angle_beta 105.00
_cell_angle_gamma 90
_cell_volume 618.296
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_symmetry_equiv_pos_as_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_Uiso_or_equiv
NiMe1   0.00000   0.00000   0.00000   0.99000 ?
MgMe1   0.00000   0.00000   0.00000   0.01000 ?
NiMe2   0.00000   0.38583   0.00000   0.82500 ?
MgMe2   0.00000   0.38583   0.00000   0.17500 ?
As   0.31620   0.00000   0.37558   1.00000 ?
O1   0.14910   0.00000   0.38070   1.00000 ?
O2   0.40720   0.00000   0.72870   1.00000 ?
O3   0.34290   0.10760   0.21040   1.00000 ?
OW1   0.09610   0.11350   0.81260   1.00000 ?
OW2   0.40010   0.22530   0.71830   1.00000 ?
H11   0.11800   0.08500   0.67400   1.00000   0.02290
H12   0.16400   0.12800   0.92400   1.00000   0.04140
H21   0.37200   0.20500   0.54500   1.00000   0.04660
H22   0.44600   0.27500   0.71100   1.00000   0.04570