data_global
_chemical_name_mineral 'Danburite'
loop_
_publ_author_name
'Sugiyama K'
'Takeuchi Y'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 173 
_journal_year 1985
_journal_page_first 293
_journal_page_last 304
_publ_section_title
;
 Unusual thermal expansion of a B-O-bond in the structure of danburite CaB2Si2O8
 Note: AnisoB's from ICSD
 Sample: T = 618 C
;
_database_code_amcsd 0010949
_chemical_compound_source 'Toroku mine, Miyazaki Prefecture, Japan'
_chemical_formula_sum 'Ca B2 Si2 O8'
_cell_length_a 8.078
_cell_length_b 8.786
_cell_length_c 7.762
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 550.895
_exptl_crystal_density_diffrn      2.964
_symmetry_space_group_name_H-M 'P n a m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,y,1/2-z'
  '-x,-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,z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ca   0.38810   0.07670   0.25000   0.02186
B   0.26080   0.41890   0.42030   0.01391
Si   0.05489   0.19258  -0.05643   0.01139
O1   0.19380   0.06810  -0.00520   0.02228
O2   0.12730   0.36460  -0.04120   0.01878
O3   0.40240   0.31450   0.07730   0.01814
O4   0.51160   0.66660   0.25000   0.02263
O5   0.18650   0.42590   0.25000   0.02213
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
Ca 0.02446 0.01955 0.02167 -0.00079 0.00000 0.00000
B 0.01554 0.01369 0.01221 -0.00036 0.00000 0.00000
Si 0.01322 0.00993 0.01099 -0.00022 0.00025 -0.00014
O1 0.02281 0.01447 0.02930 0.00683 -0.00540 -0.00345
O2 0.02116 0.01251 0.02259 -0.00467 -0.00762 0.00138
O3 0.01719 0.02034 0.01679 0.00431 0.00476 0.00311
O4 0.02777 0.02816 0.01221 0.00863 0.00000 0.00000
O5 0.01752 0.03715 0.01190 0.00539 0.00000 0.00000