data_global
_chemical_name_mineral 'Bechererite'
loop_
_publ_author_name
'Giester G'
'Rieck B'
_journal_name_full 'American Mineralogist'
_journal_volume 81 
_journal_year 1996
_journal_page_first 244
_journal_page_last 248
_publ_section_title
;
 Bechererite, (Zn,Cu)6Zn2(OH)13[(S,Si)(O,OH)4]2, a novel mineral species from the
 Tonopah-Belmont mine, Arizonia
 Note: U(1,2) changed for Si, S, O1, OH1 to match symmetry constraints.
;
_database_code_amcsd 0001776
_chemical_formula_sum 'Zn6.938 Cu1.002 (Si S) H19 O21'
_cell_length_a 8.319
_cell_length_b 8.319
_cell_length_c 7.377
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 442.133
_exptl_crystal_density_diffrn      3.503
_symmetry_space_group_name_H-M 'P -3'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'y,-x+y,-z'
  '-x+y,-x,z'
  '-x,-y,-z'
  '-y,x-y,z'
  'x-y,x,-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   0.41990   0.28530  -0.00050   0.82300 ?
Cu1   0.41990   0.28530  -0.00050   0.16700 ?
Zn2   0.00000   0.00000   0.24470   1.00000 ?
Si   0.33333   0.66667   0.40390   0.50000 ?
S   0.33333   0.66667   0.40390   0.50000 ?
H1   0.35000   0.39000   0.48000   1.00000   0.48000
H2   0.23000   0.32000   0.26000   1.00000   0.26000
H3   0.45000   0.10000   0.24000   1.00000   0.24000
O1   0.33333   0.66667   0.18600   1.00000 ?
O2   0.32800   0.48900   0.47800   1.00000 ?
O-H1   0.00000   0.00000   0.50000   1.00000 ?
O-h2   0.18900   0.24400   0.16400   1.00000 ?
O-h3   0.47800   0.10400   0.12400   1.00000 ?
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 0.01900 0.01400 0.02700 0.00900 -0.00200 0.00000
Cu1 0.01900 0.01400 0.02700 0.00900 -0.00200 0.00000
Zn2 0.02000 0.02000 0.01900 0.01000 0.00000 0.00000
Si 0.03500 0.03500 0.03300 0.01750 0.00000 0.00000
S 0.03500 0.03500 0.03300 0.01750 0.00000 0.00000
O1 0.03300 0.03300 0.04200 0.01650 0.00000 0.00000
O2 0.06500 0.02900 0.02900 0.03400 -0.00300 -0.00100
O-H1 0.14900 0.14900 0.00800 0.07450 0.00000 0.00000
O-h2 0.02500 0.03000 0.01800 0.01200 -0.00400 -0.00700
O-h3 0.02100 0.01500 0.02200 0.00500 0.00500 0.00100