data_global
_chemical_name_mineral 'Biotite'
loop_
_publ_author_name
'Brigatti M F'
'Davoli P'
_journal_name_full 'American Mineralogist'
_journal_volume 75 
_journal_year 1990
_journal_page_first 305
_journal_page_last 313
_publ_section_title
;
 Crystal-structure refinement of 1M plutonic biotites
 sample M13 from a granite in the Valle del Cervo pluton
;
_database_code_amcsd 0001296
_chemical_formula_sum 'Fe Mg2 K (Al Si3) O12'
_cell_length_a 5.355
_cell_length_b 9.251
_cell_length_c 10.246
_cell_angle_alpha 90
_cell_angle_beta 100.15
_cell_angle_gamma 90
_cell_volume 499.634
_exptl_crystal_density_diffrn      2.970
_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
Fe1   0.00000   0.00000   0.50000   1.00000
Mg2   0.00000   0.33420   0.50000   1.00000
K   0.00000   0.50000   0.00000   1.00000
Al   0.07520   0.16660   0.22560   0.25000
Si   0.07520   0.16660   0.22560   0.75000
O1   0.02410   0.00000   0.16940   1.00000
O2   0.32030   0.23550   0.16680   1.00000
O3   0.13300   0.16760   0.39160   1.00000
O4   0.13040   0.50000   0.39490   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
Fe1 0.01914 0.01864 0.02319 0.00000 0.00808 0.00000
Mg2 0.01619 0.02341 0.02267 0.00000 0.00619 0.00000
K 0.04307 0.04596 0.05153 0.00000 0.01454 0.00000
Al 0.01337 0.01517 0.02113 -0.00173 0.00646 -0.00142
Si 0.01337 0.01517 0.02113 -0.00173 0.00646 -0.00142
O1 0.03406 0.03078 0.03350 0.00000 0.00943 0.00000
O2 0.02998 0.03512 0.03298 -0.00494 0.01212 -0.00189
O3 0.01478 0.01344 0.02577 -0.00124 0.00458 0.00047
O4 0.01844 0.02081 0.01443 0.00000 0.00485 0.00000