data_global
_chemical_name_mineral 'Koenenite'
loop_
_publ_author_name
'Allmann R'
'Lohse H N'
'Hellner E'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 126 
_journal_year 1968
_journal_page_first 7
_journal_page_last 22
_publ_section_title
;
 Die kristallstruktur des koenenits, eine doppelschichtstruktur mit zwei
 inkommensurablen teilgittern
 Note: one of two substructures in koenenite
;
_database_code_amcsd 0010653
_chemical_formula_sum '(Na.667 Ca.222 Mg.111) Cl2'
_cell_length_a 4.072
_cell_length_b 4.072
_cell_length_c 32.64
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 468.701
_exptl_crystal_density_diffrn      1.040
_symmetry_space_group_name_H-M 'R -3 m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '2/3+x,1/3+y,1/3+z'
  '1/3+x,2/3+y,2/3+z'
  'x,x-y,z'
  '2/3+x,1/3+x-y,1/3+z'
  '1/3+x,2/3+x-y,2/3+z'
  'y,x,-z'
  '2/3+y,1/3+x,1/3-z'
  '1/3+y,2/3+x,2/3-z'
  '-x+y,y,z'
  '2/3-x+y,1/3+y,1/3+z'
  '1/3-x+y,2/3+y,2/3+z'
  '-x,-x+y,-z'
  '2/3-x,1/3-x+y,1/3-z'
  '1/3-x,2/3-x+y,2/3-z'
  '-y,-x,z'
  '2/3-y,1/3-x,1/3+z'
  '1/3-y,2/3-x,2/3+z'
  'x-y,-y,-z'
  '2/3+x-y,1/3-y,1/3-z'
  '1/3+x-y,2/3-y,2/3-z'
  'y,-x+y,-z'
  '2/3+y,1/3-x+y,1/3-z'
  '1/3+y,2/3-x+y,2/3-z'
  '-x+y,-x,z'
  '2/3-x+y,1/3-x,1/3+z'
  '1/3-x+y,2/3-x,2/3+z'
  '-x,-y,-z'
  '2/3-x,1/3-y,1/3-z'
  '1/3-x,2/3-y,2/3-z'
  '-y,x-y,z'
  '2/3-y,1/3+x-y,1/3+z'
  '1/3-y,2/3+x-y,2/3+z'
  'x-y,x,-z'
  '2/3+x-y,1/3+x,1/3-z'
  '1/3+x-y,2/3+x,2/3-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
Na   0.00000   0.00000   0.00000   0.66700   0.02913
Ca   0.00000   0.00000   0.00000   0.22200   0.02913
Mg   0.00000   0.00000   0.00000   0.11100   0.02913
Cl   0.66667   0.33333   0.04636   1.00000   0.04559
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
Na 0.02660 0.02660 0.04177 0.01330 0.00000 0.00000
Ca 0.02660 0.02660 0.04177 0.01330 0.00000 0.00000
Mg 0.02660 0.02660 0.04177 0.01330 0.00000 0.00000
Cl 0.04813 0.04813 0.04053 0.02406 0.00000 0.00000