data_Augite

_chemical_name_systematic          
;
Sodium calcium magnesium iron titanium alumosilicate *
;
_chemical_name_mineral             'Augite'
_chemical_compound_source          'from Kakanui, New Zealand'
_chemical_formula_structural       'Na.1 Ca.6 Mg.9 Fe.2 Ti.0 Al.34 Si1.82 O6'
_chemical_formula_analytical       
;
(Na.09 Ca.61) (Mg.90 Fe.21 Al.16) (Si1.83 Al.17 Ti.02) O6
;
_chemical_formula_sum              'Al.34 Ca.6 Fe.2 Mg.9 Na.1 O6 Si1.82'

_publ_section_title                
;
Crystal-Chemical Characterization of Clinopyroxenes based on Eight New 
Structure Refinements
;
loop_
_publ_author_name                  
  'Clark, J R'
  'Appleman, D E'
  'Papike, J J'
_journal_name_full                 
;
Mineralogical Society of America: Special Papers
;
_journal_coden_ASTM                MSAPAX
_journal_volume                    2
_journal_year                      1969
_journal_page_first                31
_journal_page_last                 50

_cell_length_a                     9.699(1)
_cell_length_b                     8.844(1)
_cell_length_c                     5.272(1)
_cell_angle_alpha                  90
_cell_angle_beta                   106.97(2)
_cell_angle_gamma                  90
_cell_volume                       432.5
_cell_formula_units_Z              4

_symmetry_space_group_name_H-M     'C 1 2/c 1'
_symmetry_Int_Tables_number        15
_symmetry_cell_setting             monoclinic

loop_
_symmetry_equiv_pos_as_xyz         
  'x,y,z'
  '-x,y,1/2-z'
  '-x,-y,-z'
  'x,-y,1/2+z'
  '1/2+x,1/2+y,z'
  '1/2-x,1/2+y,1/2-z'
  '1/2-x,1/2-y,-z'
  '1/2+x,1/2-y,1/2+z'

loop_
_atom_type_symbol
_atom_type_oxidation_number
  Na1+   1.000
  Ca2+   2.000
  Mg2+   2.000
  Fe2+   2.500
  Al3+   3.000
  Ti4+   4.000
  Si4+   4.000
  O2-   -2.000

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Na1   Na1+   4 e 0. 0.2952(1) 0.25 0.09  0 d
  Ca1   Ca2+   4 e 0. 0.2952(1) 0.25 0.616  0 d
  Mg1   Mg2+   4 e 0. 0.9063(1) 0.25 0.715  0 d
  Mg2   Mg2+   4 e 0. 0.2952(1) 0.25 0.187  0 d
  Fe1   Fe2+   4 e 0. 0.2952(1) 0.25 0.107  0 d
  Fe2   Fe2+   4 e 0. 0.9063(1) 0.25 0.103(5)  0 d
  Al1   Al3+   4 e 0. 0.9063(1) 0.25 0.182  0 d
  Al2   Al3+   8 f 0.2896(1) 0.0924(1) 0.2353(1) 0.08  0 d
  Ti1   Ti4+   8 f 0.2896(1) 0.0924(1) 0.2353(1) 0.01  0 d
  Si1   Si4+   8 f 0.2896(1) 0.0924(1) 0.2353(1) 0.91  0 d
  O1    O2-    8 f 0.1150(2) 0.0865(3) 0.1402(4) 1.  0 d
  O2    O2-    8 f 0.3647(3) 0.2530(3) 0.3260(5) 1.  0 d
  O3    O2-    8 f 0.3256(2) 0.0185(3) 0.0013(4) 1.  0 d

_refine_ls_R_factor_all            0.049



data_Augite2

_chemical_name_systematic          'Magnesium iron calcium aluminium silicate *'
_chemical_name_mineral             'Augite'
_chemical_compound_source          'from Hessereau Hill, Oka, Quebec'
_chemical_formula_structural       '(Mg.6 Fe.2 Al.2) Ca (Si1.5 Al.5) O6'
_chemical_formula_analytical       
;
(Ca.975 Na.007 Mn.007 K.001) (Mg.57 Fe.222 Al.171 Ti.065) (Si1.506 
Al.494) O6
;
_chemical_formula_sum              'Al.7 Ca Fe.2 Mg.6 O6 Si1.5'

_publ_section_title                
;
Refinement of the Crystal Structure of a Pyroxene of Formula M1 M2 
(Si1.5 Al.5) O6
;
_publ_author_name                  'Peacor, D R'
_journal_name_full                 'American Mineralogist'
_journal_coden_ASTM                AMMIAY
_journal_volume                    52
_journal_year                      1967
_journal_page_first                31
_journal_page_last                 41

_cell_length_a                     9.794(5)
_cell_length_b                     8.906(5)
_cell_length_c                     5.319(3)
_cell_angle_alpha                  90
_cell_angle_beta                   105.90(3)
_cell_angle_gamma                  90
_cell_volume                       446.2
_cell_formula_units_Z              4

_exptl_crystal_density_meas        3.4

_symmetry_space_group_name_H-M     'C 1 2/c 1'
_symmetry_Int_Tables_number        15
_symmetry_cell_setting             monoclinic

loop_
_symmetry_equiv_pos_as_xyz         
  'x,y,z'
  '-x,y,1/2-z'
  '-x,-y,-z'
  'x,-y,1/2+z'
  '1/2+x,1/2+y,z'
  '1/2-x,1/2+y,1/2-z'
  '1/2-x,1/2-y,-z'
  '1/2+x,1/2-y,1/2+z'

loop_
_atom_type_symbol
_atom_type_oxidation_number
  Mg2+   2.000
  Fe3+   3.000
  Al3+   3.000
  Ca2+   2.000
  Si4+   4.000
  O2-   -2.000

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Mg1   Mg2+   4 e 0. 0.0932(2) 0.75 0.6  0 d
  Fe1   Fe3+   4 e 0. 0.0932(2) 0.75 0.2  0 d
  Al1   Al3+   4 e 0. 0.0932(2) 0.75 0.2  0 d
  Ca1   Ca2+   4 e 0. 0.6957(2) 0.75 1.  0 d
  Si1   Si4+   8 f 0.2129(2) 0.4072(2) 0.7728(3) 0.75  0 d
  Al2   Al3+   8 f 0.2129(2) 0.4072(2) 0.7728(3) 0.25  0 d
  O1    O2-    8 f 0.3870(4) 0.4122(4) 0.8623(8) 1.  0 d
  O2    O2-    8 f 0.1379(4) 0.2454(4) 0.6811(8) 1.  0 d
  O3    O2-    8 f 0.1482(4) 0.4811(5) 0.0083(8) 1.  0 d

_refine_ls_R_factor_all            0.064