data_global
_chemical_name_mineral 'Nyerereite'
loop_
_publ_author_name
'McKie D'
'Frankis E J'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 145 
_journal_year 1977
_journal_page_first 73
_journal_page_last 95
_publ_section_title
;
 Nyerereite: A new volcanic carbonate mineral from Oldoinyo Lengai, Tanzania
 Note: high-temperature polymorph with an structure that has been inferred
;
_database_code_amcsd 0010791
_chemical_compound_source 'Oldoinyo Lengai, Tanzania'
_chemical_formula_sum 'Ca Na1.64 K.36 C2 O6'
_cell_length_a 5.05
_cell_length_b 5.05
_cell_length_c 12.85
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 283.803
_exptl_crystal_density_diffrn      2.479
_symmetry_space_group_name_H-M 'P 63 m c'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-x+y,1/2+z'
  'x-y,x,1/2+z'
  '-y,-x,z'
  '-y,x-y,z'
  'x-y,-y,1/2+z'
  '-x,-y,1/2+z'
  'x,x-y,z'
  '-x+y,-x,z'
  'y,x,1/2+z'
  'y,-x+y,1/2+z'
  '-x+y,y,z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Ca   0.00000   0.00000   0.00000   1.00000
Na   0.33333   0.66667   0.82500   0.64000
K   0.33333   0.66667   0.82500   0.36000
Na   0.33333   0.66667   0.12500   1.00000
C   0.33333   0.66667   0.50000   1.00000
C   0.00000   0.00000   0.25000   1.00000
O   0.48000   0.52000   0.50000   1.00000
O   0.15000   0.85000   0.25000   1.00000