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 = 23.6 kbar
 pyroxene
;
_database_code_amcsd 0000812
_chemical_formula_sum 'Si2 Mg Ca O6'
_cell_length_a 9.6809
_cell_length_b 8.847
_cell_length_c 5.2169
_cell_angle_alpha 90
_cell_angle_beta 105.57
_cell_angle_gamma 90
_cell_volume 430.415
_exptl_crystal_density_diffrn      3.342
_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   0.28637   0.09410   0.22850
Mg1   0.00000   0.90920   0.25000
Ca2   0.00000   0.30260   0.25000
O1   0.11520   0.08640   0.14200
O2   0.36090   0.25150   0.31920
O3   0.35170   0.01850   0.99210
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 0.00458 0.00634 0.00486 -0.00017 0.00142 -0.00068
Mg1 0.00617 0.00317 0.00461 0.00000 0.00024 0.00000
Ca2 0.01040 0.00317 0.00678 0.00000 -0.00024 0.00000
O1 0.00617 0.00040 0.00768 0.00000 0.00024 0.00045
O2 0.01013 0.01071 0.00589 -0.00125 0.00166 -0.00068
O3 0.00705 0.00991 0.00512 -0.00084 0.00142 -0.00203