data_9000149
_chemical_name 'Clinopyroxene'
loop_
_publ_author_name
'Peacor D R'
_journal_name_full "American Mineralogist"
_journal_volume 52
_journal_year 1967
_journal_page_first 31
_journal_page_last 41
_publ_section_title
;
 Refinement of the crystal structure of a pyroxene of formula M1M2(Si1.5Al0.5)O6
;
_chemical_formula_sum 'Mg.57 Fe.22 Al.64 Ti.07 (Ca.98 Mn.01 Na.01) Si1.5 O6'
_cell_length_a 9.794
_cell_length_b 8.906
_cell_length_c 5.319
_cell_angle_alpha 90
_cell_angle_beta 105.90
_cell_angle_gamma 90
_cell_volume 446.202
_symmetry_space_group_name_H-M 'C 1 2/c 1'
loop_
_symmetry_equiv_pos_as_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
_atom_site_occupancy
Mg1   0.00000   0.09320   0.75000   0.57000
Fe1   0.00000   0.09320   0.75000   0.22000
Al1   0.00000   0.09320   0.75000   0.14000
Ti1   0.00000   0.09320   0.75000   0.07000
Ca2   0.00000   0.69570   0.75000   0.98000
Mn2   0.00000   0.69570   0.75000   0.01000
Na2   0.00000   0.69570   0.75000   0.01000
Si   0.21290   0.40720   0.77280   0.75000
Al   0.21290   0.40720   0.77280   0.25000
O1   0.38700   0.41220   0.86230   1.00000
O2   0.13790   0.24540   0.68110   1.00000
O3   0.14820   0.48110   0.00830   1.00000