data_global
_chemical_name_mineral 'Kosmochlor'
loop_
_publ_author_name
'Origlieri M J'
'Downs R T'
'Thompson R M'
'Pommier C J S'
'Denton M B'
'Harlow G E'
_journal_name_full 'American Mineralogist'
_journal_volume 88 
_journal_year 2003
_journal_page_first 1025
_journal_page_last 1032
_publ_section_title
;
 High-pressure crystal structure of kosmochlor, NaCrSi2O6, and systematics of
 anisotropic compression in pyroxenes
 Sample: P = 5.05 GPa
;
_database_code_amcsd 0003137
_chemical_formula_sum 'Na Cr Si2 O6'
_cell_length_a 9.4562
_cell_length_b 8.5997
_cell_length_c 5.2016
_cell_angle_alpha 90
_cell_angle_beta 107.104
_cell_angle_gamma 90
_cell_volume 404.289
_exptl_crystal_density_diffrn      3.732
_symmetry_space_group_name_H-M 'C 1 2/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '-x,y,1/2-z'
  '1/2-x,1/2+y,1/2-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
Na2   0.00000   0.30310   0.25000   0.01900
Cr1   0.00000   0.90880   0.25000   0.00988
Si   0.29240   0.09360   0.23430   0.01203
O1   0.11600   0.07990   0.13900   0.01140
O2   0.36000   0.26110   0.31000   0.01267
O3   0.35900   0.01310   0.00500   0.01267