#------------------------------------------------------------------------------
#$Date: 2009-11-18 14:56:34 +0000 (Wed, 18 Nov 2009) $
#$Revision: 858 $
#$URL: svn://www.crystallography.net/cod/cif/2/2002783.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_2002783
_chemical_name_systematic          'Zink magnesium arsenate(V) (2.3/0.7/2)'
_chemical_formula_structural       'Zn2.28 Mg.72 (As O4)2'
_chemical_formula_sum            'As2 Mg0.72 O8 Zn2.28'
_[local]_cod_chemical_formula_sum_orig 'As2 Mg.72 O8 Zn2.28'
_publ_section_title
;
Synthese und Kristallchemie der beta-Form eines gemischten
Zinkorthoarsenats:Zn2.28 Mg0.72 (As O4)2
;
loop_
_publ_author_name
  'Mueller-Buschbaum, Hk'
  'Frerichs, D'
_journal_name_full
;
Zeitschrift fuer Naturforschung, Teil B. Anorganische Chemie,
Organische Chemie (42,1987-)
;
_journal_volume                    51
_journal_year                      1996
_journal_page_first                469
_journal_page_last                 472
_cell_length_a                     5.292(2)
_cell_length_b                     8.450(3)
_cell_length_c                     7.737(3)
_cell_angle_alpha                  90
_cell_angle_beta                   96.33(3)
_cell_angle_gamma                  90
_cell_volume                       343.9
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P 1 21/n 1'
_symmetry_Int_Tables_number        14
_symmetry_cell_setting             monoclinic
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2+x,1/2-y,1/2+z'
  '-x,-y,-z'
  '1/2-x,1/2+y,1/2-z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Zn2+   2.000
  Mg2+   2.000
  As5+   5.000
  O2-   -2.000
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Zn1   Zn2+   4 e -0.40757(11) 0.13887(7) 0.11203(7) 1.  0 d
  Zn2   Zn2+   2 b -0.5 0.5 0. 0.292(5)  0 d
  Mg2   Mg2+   2 b -0.5 0.5 0. 0.708(5)  0 d
  As1   As5+   4 e 0.04509(8) 0.30666(5) 0.19244(5) 1.  0 d
  O1    O2-    4 e -0.0662(6) 0.1289(4) 0.2547(4) 1.  0 d
  O2    O2-    4 e -0.1854(7) 0.3627(4) 0.0400(4) 1.  0 d
  O3    O2-    4 e 0.3315(6) 0.3027(4) 0.1155(4) 1.  0 d
  O4    O2-    4 e 0.0701(7) 0.4322(4) 0.3627(4) 1.  0 d
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_22
_atom_site_aniso_U_23
_atom_site_aniso_U_33
  Zn1   0.0123(2) 0.0002(2) 0.0011(2) 0.0151(2) -0.0011(2) 0.0150(2)
  Zn2   0.0093(6) 0.0013(5) 0.0027(4) 0.0153(6) -0.0003(5) 0.0118(6)
  Mg2   0.0093(6) 0.0013(5) 0.0027(4) 0.0153(6) -0.0003(5) 0.0118(6)
  As1   0.00671(14) -0.00032(15) 0.00295(11) 0.00971(15) -0.00075(14) 0.00795(14
  O1    0.0162(13) -0.0014(11) 0.0032(11) 0.0176(13) -0.0005(11) 0.0233(14)
  O2    0.0162(14) 0.0021(12) 0.0001(11) 0.030(2) -0.0042(12) 0.0213(14)
  O3    0.0189(13) 0.0055(12) 0.0132(11) 0.0226(13) 0.0032(12) 0.0260(14)
  O4    0.029(2) 0.0023(13) 0.0031(11) 0.0207(14) -0.0037(11) 0.0150(13)
_refine_ls_R_factor_all            0.1058