data_global
_chemical_name_mineral 'Superhydrous Phase B'
loop_
_publ_author_name
'Koch-Muller M'
'Dera P'
'Fei Y'
'Hellwig H'
'Liu Z'
'Van Orman J'
'Wirth R'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 32 
_journal_year 2005
_journal_page_first 349
_journal_page_last 361
_publ_section_title
;
 Polymorphic phase transition in Superhydrous Phase B
 Sample: JIM252
;
_database_code_amcsd 0008973
_chemical_formula_sum '(Mg8.2 Ni1.8) Si3 O18 (D3.2 H.8)'
_cell_length_a 13.991
_cell_length_b 5.097
_cell_length_c 8.715
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 621.485
_exptl_crystal_density_diffrn      3.657
_symmetry_space_group_name_H-M 'P n n m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2-y,1/2+z'
  '1/2-x,1/2+y,1/2-z'
  '1/2-x,1/2+y,1/2+z'
  '1/2+x,1/2-y,1/2-z'
  'x,y,-z'
  '-x,-y,z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Mg1   0.17290   0.33010   0.00000   0.82000
Ni1   0.17290   0.33010   0.00000   0.18000
Mg2   0.17580   0.84100   0.17560   0.82000
Ni2   0.17580   0.84100   0.17560   0.18000
Mg3   0.00000   0.00000   0.34130   0.82000
Ni3   0.00000   0.00000   0.34130   0.18000
Mg4   0.00000   0.50000   0.17760   0.82000
Ni4   0.00000   0.50000   0.17760   0.18000
Si1   0.00000   0.00000   0.00000   1.00000
Si2   0.37650   0.01440   0.00000   1.00000
O1   0.25190   0.51490   0.15790   1.00000
O2   0.41520   0.71030   0.00000   1.00000
O3   0.07870   0.69930   0.00000   1.00000
O4   0.07310   0.14280   0.14520   1.00000
O5   0.41340   0.16720   0.15550   1.00000
O6   0.25770   0.00510   0.00000   1.00000
D1   0.30000   0.60000   0.10000   0.80000
H1   0.30000   0.60000   0.10000   0.20000