data_global
_chemical_name_mineral 'Diopside'
loop_
_publ_author_name
'Levien L'
'Prewitt C T'
_journal_name_full 'American Mineralogist'
_journal_volume 66 
_journal_year 1981
_journal_page_first 315
_journal_page_last 323
_publ_section_title
;
 High-pressure structural study of diopside
 P = 1 atm
 pyroxene
;
_database_code_amcsd 0000811
_chemical_formula_sum 'Si2 Mg Ca O6'
_cell_length_a 9.7456
_cell_length_b 8.9198
_cell_length_c 5.2516
_cell_angle_alpha 90
_cell_angle_beta 105.86
_cell_angle_gamma 90
_cell_volume 439.137
_exptl_crystal_density_diffrn      3.275
_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
Si   0.28627   0.09330   0.22936
Mg1   0.00000   0.90814   0.25000
Ca2   0.00000   0.30144   0.25000
O1   0.11550   0.08728   0.14220
O2   0.36136   0.25013   0.31830
O3   0.35083   0.01759   0.99530
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
Si 0.00432 0.00480 0.00401 -0.00021 0.00096 -0.00016
Mg1 0.00503 0.00455 0.00388 0.00000 0.00055 0.00000
Ca2 0.00997 0.00661 0.00608 0.00000 -0.00036 0.00000
O1 0.00508 0.00774 0.00608 0.00034 0.00098 0.00039
O2 0.00984 0.00693 0.00763 -0.00165 0.00192 -0.00068
O3 0.00654 0.00867 0.00621 -0.00013 0.00192 -0.00192