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 = 53.0  kbar
 pyroxene
;
_database_code_amcsd 0000815
_chemical_formula_sum 'Si2 Mg Ca O6'
_cell_length_a 9.612
_cell_length_b 8.765
_cell_length_c 5.1793
_cell_angle_alpha 90
_cell_angle_beta 105.32
_cell_angle_gamma 90
_cell_volume 420.846
_exptl_crystal_density_diffrn      3.418
_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   0.28640   0.09460   0.22790
Mg1   0.00000   0.90970   0.25000
Ca2   0.00000   0.30400   0.25000
O1   0.11470   0.08800   0.14140
O2   0.36080   0.25420   0.32120
O3   0.35270   0.02130   0.98890
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 0.00348 0.00506 0.00392 -0.00045 0.00094 -0.00067
Mg1 0.00479 0.00545 0.00354 0.00000 0.00070 0.00000
Ca2 0.00914 0.00623 0.00518 0.00000 0.00000 0.00000
O1 0.00610 0.00701 0.00581 0.00041 0.00188 -0.00111
O2 0.00653 0.00739 0.00632 -0.00123 0.00094 -0.00067
O3 0.00697 0.00778 0.00493 -0.00041 0.00141 -0.00111