data_global
_chemical_name_mineral 'Borcarite'
loop_
_publ_author_name
'Yamnova N A'
'Simonov M A'
'Kazanskaya E V'
'Belov N V'
_journal_name_full 'Soviet Physics Doklady'
_journal_volume 20 
_journal_year 1975
_journal_page_first 799
_journal_page_last 801
_publ_section_title
;
 Refinement of the crystal structure of the Ca, Mg-carbonatoborate
 borcarite Ca4Mg/B4O6(OH)6/(CO3)2
;
_database_code_amcsd 0020477
_chemical_compound_source 'Solongo metasomatite deposit, Buryatia, Russia'
_chemical_formula_sum 'Ca4 Mg B4 C2 O18 H6'
_cell_length_a 4.445
_cell_length_b 17.843
_cell_length_c 8.378
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 101.94
_cell_volume 650.101
_exptl_crystal_density_diffrn      2.789
_symmetry_space_group_name_H-M 'A 1 1 2/m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2+y,1/2+z'
  'x,y,-z'
  'x,1/2+y,1/2-z'
  '-x,-y,z'
  '-x,1/2-y,1/2+z'
  '-x,-y,-z'
  '-x,1/2-y,1/2-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ca1   0.15480   0.15531   0.23368   0.00849
Mg1   0.00000   0.00000   0.00000   0.00646
B1   0.50000   0.00000   0.24080   0.00697
B2   0.61810   0.09490   0.00000   0.00747
C1   0.75090   0.19540   0.50000   0.00912
O1   0.30740   0.09920   0.00000   0.00823
O2   0.72030   0.05490   0.14260   0.00773
O-H3   0.30950   0.04150   0.33910   0.00963
O4   0.64650   0.21530   0.36590   0.01798
O-H5   0.82300   0.17420   0.00000   0.00937
O6   0.96170   0.15660   0.50000   0.01570
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
Ca1 0.01076 0.00695 0.00779 0.00096 -0.00103 -0.00044
Mg1 0.00583 0.00432 0.00964 0.00046 0.00000 0.00000
B1 0.00811 0.00618 0.00779 0.00023 0.00000 0.00000
B2 0.00646 0.00710 0.00871 0.00046 0.00000 0.00000
C1 0.00860 0.00726 0.01138 -0.00196 0.00000 0.00000
O1 0.00697 0.00772 0.01017 0.00112 0.00000 0.00000
O2 0.00811 0.00695 0.00765 -0.00012 -0.00013 0.00096
O-H3 0.00988 0.00988 0.00939 0.00346 0.00142 -0.00185
O4 0.02127 0.01235 0.02102 -0.00346 -0.01139 0.00608
O-H5 0.00911 0.00587 0.01376 -0.00012 0.00000 0.00000
O6 0.01494 0.01745 0.01693 0.00704 0.00000 0.00000