data_global
_chemical_name_mineral 'Enstatite'
loop_
_publ_author_name
'Hugh-Jones D A'
'Chopelas A'
'Angel R J'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 24 
_journal_year 1997
_journal_page_first 301
_journal_page_last 310
_publ_section_title
;
 Tetrahedral compression in (Mg,Fe)SiO3 orthopyroxenes
 Sample: P = 6.59 GPa, synthetic En60 orthopyroxene
;
_database_code_amcsd 0008016
_chemical_formula_sum '(Mg.59 Fe.41) Si O3'
_cell_length_a 18.0665
_cell_length_b 8.706
_cell_length_c 5.1236
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 805.875
_exptl_crystal_density_diffrn      3.736
_symmetry_space_group_name_H-M 'P b c a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2-y,1/2+z'
  '-x,1/2+y,1/2-z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,-z'
  '1/2+x,y,1/2-z'
  '1/2-x,-y,1/2+z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
MgM1   0.37630   0.65760   0.86120   0.59000   0.00076
FeM1   0.37630   0.65760   0.86120   0.41000   0.00076
MgM2   0.37830   0.48020   0.35440   0.59000   0.00076
FeM2   0.37830   0.48020   0.35440   0.41000   0.00076
SiTA   0.27120   0.34130   0.03930   1.00000   0.00013
SiTB   0.47290   0.33770   0.80100   1.00000   0.00025
O1a   0.18270   0.34000   0.02800   1.00000   0.00063
O2a   0.30910   0.50600   0.04000   1.00000   0.00127
O3a   0.30430   0.23000   0.81500   1.00000   0.00089
O1b   0.56140   0.33900   0.80600   1.00000   0.00076
O2b   0.43370   0.48500   0.68700   1.00000   0.00089
O3b   0.44540   0.19400   0.60800   1.00000   0.00304