data_global
_chemical_name_mineral 'Borcarite'
loop_
_publ_author_name
'Burns P C'
'Hawthorne F C'
_journal_name_full 'Mineralogical Magazine'
_journal_volume 59 
_journal_year 1995
_journal_page_first 297
_journal_page_last 304
_publ_section_title
;
 Hydrogen bonding in borcarite, an unusual borate-carbonate mineral
;
_database_code_amcsd 0014516
_chemical_compound_source 'Yakutskaya, Russia'
_chemical_formula_sum 'Ca4 Mg B4 C2 O18 H6'
_cell_length_a 17.840
_cell_length_b 8.380
_cell_length_c 4.445
_cell_angle_alpha 90
_cell_angle_beta 102.04
_cell_angle_gamma 90
_cell_volume 649.906
_exptl_crystal_density_diffrn      2.790
_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_U_iso_or_equiv
Ca   0.15543   0.23368   0.15480 ?
Mg   0.00000   0.00000   0.00000 ?
B1   0.00000   0.24000   0.50000 ?
B2   0.09480   0.00000   0.61710 ?
C   0.30480   0.00000   0.25150 ?
O1   0.09940   0.00000   0.30710 ?
O2   0.05513   0.14270   0.72040 ?
O-h3   0.04149   0.33850   0.30950 ?
O4   0.21500   0.36540   0.64870 ?
O-h5   0.17430   0.00000   0.82360 ?
O6   0.34410   0.00000   0.03980 ?
H1   0.00500   0.35500   0.12700   0.03000
H2   0.21200   0.00000   0.69800   0.03000
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 0.00810 0.00770 0.01090 -0.00080 0.00150 -0.00120
Mg 0.00460 0.00720 0.00400 0.00000 0.00100 0.00000
B1 0.01240 0.01250 0.01390 0.00000 0.00230 0.00000
B2 0.00650 0.00840 0.00820 0.00000 -0.00050 0.00000
C 0.00830 0.01250 0.00920 0.00000 -0.00240 0.00000
O1 0.00910 0.00970 0.00670 0.00000 0.00150 0.00000
O2 0.00880 0.00770 0.00730 0.00170 0.00040 0.00010
O-h3 0.01050 0.00900 0.01000 -0.00120 0.00300 0.00140
O4 0.01430 0.02060 0.02210 0.00570 -0.00360 -0.01180
O-h5 0.00710 0.01370 0.00930 0.00000 0.00070 0.00000
O6 0.02460 0.01550 0.01560 0.00000 0.01050 0.00000