data_global
_chemical_name_mineral 'Biotite'
loop_
_publ_author_name
'Bigi S'
'Brigatti M F'
_journal_name_full 'American Mineralogist'
_journal_volume 79 
_journal_year 1994
_journal_page_first 63
_journal_page_last 72
_publ_section_title
;
 Crystal chemistry and microstructures of plutonic biotite
 Sample 1M from Valle del Cervo syenitic complex
;
_database_code_amcsd 0001633
_chemical_formula_sum 'Si2.808 Al1.207 Fe.4 Mg.512 Mn.007 Ti.067 Na.034 K1.906 O12'
_cell_length_a 5.335
_cell_length_b 9.244
_cell_length_c 10.206
_cell_angle_alpha 90
_cell_angle_beta 100.08
_cell_angle_gamma 90
_cell_volume 495.558
_exptl_crystal_density_diffrn      2.795
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
SiT   0.07520   0.16690   0.22580   0.70200
AlT   0.07520   0.16690   0.22580   0.29800
Al1   0.00000   0.00000   0.50000   0.01500
Fe1   0.00000   0.00000   0.50000   0.40000
Mg1   0.00000   0.00000   0.50000   0.51200
Mn1   0.00000   0.00000   0.50000   0.00700
Ti1   0.00000   0.00000   0.50000   0.06700
Na2   0.00000   0.33430   0.50000   0.01700
K2   0.00000   0.33430   0.50000   0.95300
O1   0.02470   0.00000   0.16880   1.00000
O2   0.32190   0.23360   0.16830   1.00000
O3   0.13340   0.16750   0.39050   1.00000
O4   0.13010   0.50000   0.39520   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
SiT 0.02250 0.01645 0.02660 -0.00049 0.00562 0.00047
AlT 0.02250 0.01645 0.02660 -0.00049 0.00562 0.00047
Al1 0.02404 0.01645 0.03427 0.00000 0.00963 0.00000
Fe1 0.02404 0.01645 0.03427 0.00000 0.00963 0.00000
Mg1 0.02404 0.01645 0.03427 0.00000 0.00963 0.00000
Mn1 0.02404 0.01645 0.03427 0.00000 0.00963 0.00000
Ti1 0.02404 0.01645 0.03427 0.00000 0.00963 0.00000
Na2 0.02236 0.01905 0.03069 0.00000 0.00749 0.00000
K2 0.02236 0.01905 0.03069 0.00000 0.00749 0.00000
O1 0.04277 0.02035 0.03632 0.00000 0.00562 0.00000
O2 0.02963 0.03810 0.03376 -0.00541 0.00909 -0.00282
O3 0.02754 0.01905 0.03120 0.00000 0.00775 0.00188
O4 0.02768 0.02294 0.03274 0.00000 0.00722 0.00000