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 = 45.5 kbar
 pyroxene
;
_database_code_amcsd 0000814
_chemical_formula_sum 'Si2 Mg Ca O6'
_cell_length_a 9.630
_cell_length_b 8.785
_cell_length_c 5.1895
_cell_angle_alpha 90
_cell_angle_beta 105.37
_cell_angle_gamma 90
_cell_volume 423.327
_exptl_crystal_density_diffrn      3.398
_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   0.28630   0.09449   0.22790
Mg1   0.00000   0.90940   0.25000
Ca2   0.00000   0.30378   0.25000
O1   0.11500   0.08790   0.14210
O2   0.36110   0.25340   0.32010
O3   0.35300   0.02070   0.99010
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 0.00349 0.00430 0.00330 -0.00058 0.00094 -0.00022
Mg1 0.00393 0.00430 0.00304 0.00000 0.00071 0.00000
Ca2 0.00874 0.00508 0.00495 0.00000 0.00000 0.00000
O1 0.00437 0.00626 0.00558 0.00041 0.00141 0.00000
O2 0.00612 0.00743 0.00723 -0.00248 0.00282 -0.00089
O3 0.00437 0.00821 0.00482 -0.00124 0.00188 -0.00200