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 = 25 C
;
_database_code_amcsd 0010946
_chemical_compound_source 'Toroku mine, Miyazaki Prefecture, Japan'
_chemical_formula_sum 'Ca B2 Si2 O8'
_cell_length_a 8.037
_cell_length_b 8.757
_cell_length_c 7.7218
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 543.460
_exptl_crystal_density_diffrn      3.005
_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   0.38555   0.07648   0.25000   0.00651
B   0.25890   0.41920   0.42060   0.00540
Si   0.05333   0.19250  -0.05574   0.00374
O1   0.19291   0.06797  -0.00324   0.00759
O2   0.12632   0.36496  -0.04233   0.00631
O3   0.39965   0.31351   0.07820   0.00621
O4   0.51370   0.66400   0.25000   0.00773
O5   0.18380   0.42820   0.25000   0.00747
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 0.00756 0.00606 0.00589 0.00021 0.00000 0.00000
B 0.00573 0.00579 0.00462 -0.00018 -0.00006 -0.00021
Si 0.00438 0.00357 0.00323 -0.00007 0.00006 -0.00014
O1 0.00812 0.00536 0.00927 0.00250 -0.00230 -0.00151
O2 0.00726 0.00478 0.00692 -0.00143 -0.00239 0.00027
O3 0.00586 0.00730 0.00547 0.00160 0.00154 0.00069
O4 0.00962 0.01045 0.00311 0.00250 0.00000 0.00000
O5 0.00579 0.01259 0.00405 0.00182 0.00000 0.00000