data_global
_chemical_name_mineral 'Wadsleyite'
loop_
_publ_author_name
'Smyth J R'
'Kawamoto T'
'Jacobsen S D'
'Swope R J'
'Hervig R L'
'Holloway J R'
_journal_name_full 'American Mineralogist'
_journal_volume 82 
_journal_year 1997
_journal_page_first 270
_journal_page_last 275
_publ_section_title
;
 Crystal structure of monoclinic hydrous wadsleyite [beta-(Mg,Fe)2SiO4]
 Note: occupancies of octahedral sites are estimates
;
_database_code_amcsd 0001873
_chemical_formula_sum 'Mg3.44 Si1.888 H.355 O8'
_cell_length_a 5.6715
_cell_length_b 11.582
_cell_length_c 8.258
_cell_angle_alpha 90
_cell_angle_beta 90.397
_cell_angle_gamma 90
_cell_volume 542.433
_exptl_crystal_density_diffrn      3.245
_symmetry_space_group_name_H-M 'I 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  'x,1/2-y,z'
  '1/2+x,-y,1/2+z'
  '1/2-x,y,1/2-z'
  '-x,1/2+y,-z'
  '1/2-x,1/2-y,1/2-z'
  '-x,-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
Mg1   0.00000   0.00000   0.00000   0.92000 ?
Mg2   0.00120   0.25000   0.97090   0.92000 ?
Mg3a   0.25000   0.12220   0.25000   0.77000 ?
Mg3b   0.75000   0.37830   0.25000   0.83000 ?
Si1   0.00020   0.12123   0.61558   0.92000 ?
Si2   0.49800   0.13700   0.12800   0.02400   0.01400
H1   0.01600   0.25000   0.28500   0.35500   0.05000
O1  -0.00060   0.25000   0.22560   1.00000 ?
O2  -0.00080   0.25000   0.71660   1.00000 ?
O3   0.00070   0.01240   0.74360   1.00000 ?
O4a   0.26010   0.12420   0.99460   1.00000 ?
O4b   0.74120   0.37590   0.99560   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
Mg1 0.02420 0.01170 0.02470 0.00060 0.00330 0.00350
Mg2 0.01630 0.01040 0.01230 0.00000 0.00010 0.00000
Mg3a 0.01390 0.01750 0.01370 0.00000 -0.00150 0.00000
Mg3b 0.01490 0.01670 0.01300 0.00000 0.00190 0.00000
Si1 0.00960 0.00660 0.00880 0.00030 0.00000 -0.00040
O1 0.01200 0.01600 0.01700 0.00000 0.00000 0.00000
O2 0.01500 0.01170 0.01330 0.00000 0.00040 0.00000
O3 0.01600 0.01570 0.01600 0.00020 -0.00080 -0.00010
O4a 0.01340 0.01000 0.01660 0.00040 -0.00060 0.00080
O4b 0.01310 0.00960 0.01590 0.00050 0.00010 0.00000