data_global
_chemical_name_mineral 'Fairchildite'
loop_
_publ_author_name
'Pertlik F'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 157 
_journal_year 1981
_journal_page_first 199
_journal_page_last 205
_publ_section_title
;
 Structural investigations of synthetic fairchildite, K2Ca(CO3)2
 Note: y(O1) changed to satisfy symmetry constraints
;
_database_code_amcsd 0010845
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'K2 Ca C2 O6'
_cell_length_a 5.294
_cell_length_b 5.294
_cell_length_c 13.355
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 324.147
_exptl_crystal_density_diffrn      2.441
_symmetry_space_group_name_H-M 'P 63/m m c'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-x+y,1/2+z'
  'x,x-y,1/2-z'
  '-x+y,-x,1/2-z'
  'x-y,x,1/2+z'
  '-y,-x,z'
  'y,x,-z'
  'y,-x+y,-z'
  '-y,x-y,z'
  'x-y,-y,1/2+z'
  '-x+y,y,1/2-z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  'x,x-y,z'
  '-x,-x+y,-z'
  'x-y,x,-z'
  '-x+y,-x,z'
  'y,x,1/2+z'
  '-y,-x,1/2-z'
  '-y,x-y,1/2-z'
  'y,-x+y,1/2+z'
  '-x+y,y,z'
  'x-y,-y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
KMe1   0.33333   0.66667   0.09960   1.00000   0.01418
CaMe2   0.00000   0.00000   0.25000   1.00000   0.01684
C1   0.33333   0.66667   0.75000   1.00000   0.01786
C2   0.00000   0.00000   0.00000   1.00000   0.01343
O1   0.52649   0.05298   0.25000   1.00000   0.02343
O2   0.08650   0.17300   0.92240   0.33333   0.03673
O3   0.23800   0.00000   0.00000   0.16667   0.03673
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
KMe1 0.01651 0.01661 0.02078 0.00825 0.00000 0.00000
CaMe2 0.02513 0.02513 0.01717 0.01257 0.00000 0.00000
C1 0.01459 0.01459 0.03434 0.00729 0.00000 0.00000
C2 0.02769 0.02769 0.00361 0.01384 0.00000 0.00000
O1 0.02641 0.01374 0.03524 0.00687 0.00000 0.00000