data_1001661
_chemical_name_systematic          'Dilead magnesium tungstate - II'
_chemical_formula_structural       'Pb2 Mg (W O6)'
_chemical_formula_sum              'Mg O6 Pb2 W'
_publ_section_title
;
Crystal structure of the antiferroelectric perovskite Pb2 Mg W O6
;
loop_
_publ_author_name
  'Baldinozzi, G'
  'Sciau, Ph'
  'Pinot, M'
  'Grebille, D'
_journal_name_full                 'Acta Crystallographica B (39,1983-)'
_journal_coden_ASTM                ASBSDK
_journal_volume                    51
_journal_year                      1995
_journal_page_first                668
_journal_page_last                 673
_cell_length_a                     7.9440(4)
_cell_length_b                     5.6866(3)
_cell_length_c                     11.4059(4)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       515.3
_cell_formula_units_Z              4
_symmetry_space_group_name_H-M     'P m c n'
_symmetry_Int_Tables_number        62
_symmetry_cell_setting             orthorhombic
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2-x,1/2-y,1/2+z'
  '1/2+x,-y,-z'
  '-x,1/2+y,1/2-z'
  '-x,-y,-z'
  '1/2+x,1/2+y,1/2-z'
  '1/2-x,y,z'
  'x,1/2-y,1/2+z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Pb2+   2.000
  Mg2+   2.000
  W6+    6.000
  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
  Pb1   Pb2+   8 d 0.0032(4) 0.7804(2) 0.1422(1) 1.  0 d
  Mg1   Mg2+   4 c 0.25 0.7519(9) 0.3772(4) 1.  0 d
  W1    W6+    4 c 0.25 0.2577(6) 0.1161(2) 1.  0 d
  O1    O2-    8 d 0.4907(14) 0.2365(4) 0.1314(2) 1.  0 d
  O2    O2-    4 c 0.25 0.0133(12) 0.0027(6) 1.  0 d
  O3    O2-    4 c 0.25 0.4991(17) 0.0103(5) 1.  0 d
  O4    O2-    4 c 0.25 -0.0153(15) 0.2370(4) 1.  0 d
  O5    O2-    4 c 0.25 0.4745(15) 0.2491(5) 1.  0 d
_refine_ls_R_factor_all            0.04