data_Al2O3

_chemical_name_systematic          'Aluminium oxide'
_chemical_formula_structural       'Al2 O3'
_chemical_formula_sum              'Al2 O3'

_publ_section_title                
;
Neutron diffraction measurements of the residual stresses in Al2 O3 - 
Zr O2 (Ce O2) ceramic composites
;
loop_
_publ_author_name                  
  'Wang, X - L'
  'Hubbard, C R'
  'Alexander, K B'
  'Becher, P F'
_journal_name_full                 'Journal of the American Ceramic Society'
_journal_coden_ASTM                JACTAW
_journal_volume                    77
_journal_year                      1994
_journal_page_first                1569
_journal_page_last                 1575
_journal_issue                     6

_cell_length_a                     4.7554(3)
_cell_length_b                     4.7554(3)
_cell_length_c                     12.9910(6)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  120
_cell_volume                       254.4
_cell_formula_units_Z              6

_symmetry_space_group_name_H-M     'R -3 c H'
_symmetry_Int_Tables_number        167
_symmetry_cell_setting             trigonal

loop_
_symmetry_equiv_pos_as_xyz         
  'x,y,z'
  '-y,x-y,z'
  'y-x,-x,z'
  '-y,-x,1/2+z'
  'x,x-y,1/2+z'
  'y-x,y,1/2+z'
  '-x,-y,-z'
  'y,y-x,-z'
  'x-y,x,-z'
  'y,x,1/2-z'
  '-x,y-x,1/2-z'
  'x-y,-y,1/2-z'
  '1/3+x,2/3+y,2/3+z'
  '2/3+x,1/3+y,1/3+z'
  '1/3-y,2/3+x-y,2/3+z'
  '2/3-y,1/3+x-y,1/3+z'
  '1/3-x+y,2/3-x,2/3+z'
  '2/3-x+y,1/3-x,1/3+z'
  '1/3-y,2/3-x,1/6+z'
  '2/3-y,1/3-x,5/6+z'
  '1/3+x,2/3+x-y,1/6+z'
  '2/3+x,1/3+x-y,5/6+z'
  '1/3-x+y,2/3+y,1/6+z'
  '2/3-x+y,1/3+y,5/6+z'
  '1/3-x,2/3-y,2/3-z'
  '2/3-x,1/3-y,1/3-z'
  '1/3+y,2/3-x+y,2/3-z'
  '2/3+y,1/3-x+y,1/3-z'
  '1/3+x-y,2/3+x,2/3-z'
  '2/3+x-y,1/3+x,1/3-z'
  '1/3+y,2/3+x,1/6-z'
  '2/3+y,1/3+x,5/6-z'
  '1/3-x,2/3-x+y,1/6-z'
  '2/3-x,1/3-x+y,5/6-z'
  '1/3+x-y,2/3-y,1/6-z'
  '2/3+x-y,1/3-y,5/6-z'

loop_
_atom_type_symbol
_atom_type_oxidation_number
  Al3+   3.000
  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
  Al1   Al3+  12 c 0. 0. 0.3520(3) 1.  0 d
  O1    O2-   18 e 0.3063(4) 0. 0.25 1.  0 d

_refine_ls_R_factor_all            0.07



data_Al2O3

_chemical_name_systematic          'Aluminium oxide - $-eta'
_chemical_formula_structural       'Al2.66 O4'
_chemical_formula_sum              'Al2.66 O4'

_publ_section_title                
;
The preparation of $-eta alumina and its structure
;
loop_
_publ_author_name                  
  'SHIRASUKA, K'
  'Yanagida, H'
  'Yamaguchi, G'
_journal_name_full                 
;
Yogyo Kyokai Shi (= Journal of the Ceramic Assoc. of Japan)
;
_journal_coden_ASTM                YGKSA4
_journal_volume                    84
_journal_year                      1976
_journal_page_first                610
_journal_page_last                 613

_cell_length_a                     7.906
_cell_length_b                     7.906
_cell_length_c                     7.906
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       494.2
_cell_formula_units_Z              8

_exptl_crystal_density_meas        3.66

_symmetry_space_group_name_H-M     'F d -3 m S'
_symmetry_Int_Tables_number        227
_symmetry_cell_setting             cubic

loop_
_symmetry_equiv_pos_as_xyz         
  'x,y,z'
  'y,z,x'
  'z,x,y'
  'x,z,y'
  'y,x,z'
  'z,y,x'
  'x,-y,-z'
  'y,-z,-x'
  'z,-x,-y'
  'x,-z,-y'
  'y,-x,-z'
  'z,-y,-x'
  '-x,y,-z'
  '-y,z,-x'
  '-z,x,-y'
  '-x,z,-y'
  '-y,x,-z'
  '-z,y,-x'
  '-x,-y,z'
  '-y,-z,x'
  '-z,-x,y'
  '-x,-z,y'
  '-y,-x,z'
  '-z,-y,x'
  '1/4-x,1/4-y,1/4-z'
  '1/4-y,1/4-z,1/4-x'
  '1/4-z,1/4-x,1/4-y'
  '1/4-x,1/4-z,1/4-y'
  '1/4-y,1/4-x,1/4-z'
  '1/4-z,1/4-y,1/4-x'
  '1/4-x,1/4+y,1/4+z'
  '1/4-y,1/4+z,1/4+x'
  '1/4-z,1/4+x,1/4+y'
  '1/4-x,1/4+z,1/4+y'
  '1/4-y,1/4+x,1/4+z'
  '1/4-z,1/4+y,1/4+x'
  '1/4+x,1/4-y,1/4+z'
  '1/4+y,1/4-z,1/4+x'
  '1/4+z,1/4-x,1/4+y'
  '1/4+x,1/4-z,1/4+y'
  '1/4+y,1/4-x,1/4+z'
  '1/4+z,1/4-y,1/4+x'
  '1/4+x,1/4+y,1/4-z'
  '1/4+y,1/4+z,1/4-x'
  '1/4+z,1/4+x,1/4-y'
  '1/4+x,1/4+z,1/4-y'
  '1/4+y,1/4+x,1/4-z'
  '1/4+z,1/4+y,1/4-x'
  'x,1/2+y,1/2+z'
  '1/2+x,y,1/2+z'
  '1/2+x,1/2+y,z'
  'y,1/2+z,1/2+x'
  '1/2+y,z,1/2+x'
  '1/2+y,1/2+z,x'
  'z,1/2+x,1/2+y'
  '1/2+z,x,1/2+y'
  '1/2+z,1/2+x,y'
  'x,1/2+z,1/2+y'
  '1/2+x,z,1/2+y'
  '1/2+x,1/2+z,y'
  'y,1/2+x,1/2+z'
  '1/2+y,x,1/2+z'
  '1/2+y,1/2+x,z'
  'z,1/2+y,1/2+x'
  '1/2+z,y,1/2+x'
  '1/2+z,1/2+y,x'
  'x,1/2-y,1/2-z'
  '1/2+x,-y,1/2-z'
  '1/2+x,1/2-y,-z'
  'y,1/2-z,1/2-x'
  '1/2+y,-z,1/2-x'
  '1/2+y,1/2-z,-x'
  'z,1/2-x,1/2-y'
  '1/2+z,-x,1/2-y'
  '1/2+z,1/2-x,-y'
  'x,1/2-z,1/2-y'
  '1/2+x,-z,1/2-y'
  '1/2+x,1/2-z,-y'
  'y,1/2-x,1/2-z'
  '1/2+y,-x,1/2-z'
  '1/2+y,1/2-x,-z'
  'z,1/2-y,1/2-x'
  '1/2+z,-y,1/2-x'
  '1/2+z,1/2-y,-x'
  '-x,1/2+y,1/2-z'
  '1/2-x,y,1/2-z'
  '1/2-x,1/2+y,-z'
  '-y,1/2+z,1/2-x'
  '1/2-y,z,1/2-x'
  '1/2-y,1/2+z,-x'
  '-z,1/2+x,1/2-y'
  '1/2-z,x,1/2-y'
  '1/2-z,1/2+x,-y'
  '-x,1/2+z,1/2-y'
  '1/2-x,z,1/2-y'
  '1/2-x,1/2+z,-y'
  '-y,1/2+x,1/2-z'
  '1/2-y,x,1/2-z'
  '1/2-y,1/2+x,-z'
  '-z,1/2+y,1/2-x'
  '1/2-z,y,1/2-x'
  '1/2-z,1/2+y,-x'
  '-x,1/2-y,1/2+z'
  '1/2-x,-y,1/2+z'
  '1/2-x,1/2-y,z'
  '-y,1/2-z,1/2+x'
  '1/2-y,-z,1/2+x'
  '1/2-y,1/2-z,x'
  '-z,1/2-x,1/2+y'
  '1/2-z,-x,1/2+y'
  '1/2-z,1/2-x,y'
  '-x,1/2-z,1/2+y'
  '1/2-x,-z,1/2+y'
  '1/2-x,1/2-z,y'
  '-y,1/2-x,1/2+z'
  '1/2-y,-x,1/2+z'
  '1/2-y,1/2-x,z'
  '-z,1/2-y,1/2+x'
  '1/2-z,-y,1/2+x'
  '1/2-z,1/2-y,x'
  '1/4-x,3/4-y,3/4-z'
  '3/4-x,1/4-y,3/4-z'
  '3/4-x,3/4-y,1/4-z'
  '1/4-y,3/4-z,3/4-x'
  '3/4-y,1/4-z,3/4-x'
  '3/4-y,3/4-z,1/4-x'
  '1/4-z,3/4-x,3/4-y'
  '3/4-z,1/4-x,3/4-y'
  '3/4-z,3/4-x,1/4-y'
  '1/4-x,3/4-z,3/4-y'
  '3/4-x,1/4-z,3/4-y'
  '3/4-x,3/4-z,1/4-y'
  '1/4-y,3/4-x,3/4-z'
  '3/4-y,1/4-x,3/4-z'
  '3/4-y,3/4-x,1/4-z'
  '1/4-z,3/4-y,3/4-x'
  '3/4-z,1/4-y,3/4-x'
  '3/4-z,3/4-y,1/4-x'
  '1/4-x,3/4+y,3/4+z'
  '3/4-x,1/4+y,3/4+z'
  '3/4-x,3/4+y,1/4+z'
  '1/4-y,3/4+z,3/4+x'
  '3/4-y,1/4+z,3/4+x'
  '3/4-y,3/4+z,1/4+x'
  '1/4-z,3/4+x,3/4+y'
  '3/4-z,1/4+x,3/4+y'
  '3/4-z,3/4+x,1/4+y'
  '1/4-x,3/4+z,3/4+y'
  '3/4-x,1/4+z,3/4+y'
  '3/4-x,3/4+z,1/4+y'
  '1/4-y,3/4+x,3/4+z'
  '3/4-y,1/4+x,3/4+z'
  '3/4-y,3/4+x,1/4+z'
  '1/4-z,3/4+y,3/4+x'
  '3/4-z,1/4+y,3/4+x'
  '3/4-z,3/4+y,1/4+x'
  '1/4+x,3/4-y,3/4+z'
  '3/4+x,1/4-y,3/4+z'
  '3/4+x,3/4-y,1/4+z'
  '1/4+y,3/4-z,3/4+x'
  '3/4+y,1/4-z,3/4+x'
  '3/4+y,3/4-z,1/4+x'
  '1/4+z,3/4-x,3/4+y'
  '3/4+z,1/4-x,3/4+y'
  '3/4+z,3/4-x,1/4+y'
  '1/4+x,3/4-z,3/4+y'
  '3/4+x,1/4-z,3/4+y'
  '3/4+x,3/4-z,1/4+y'
  '1/4+y,3/4-x,3/4+z'
  '3/4+y,1/4-x,3/4+z'
  '3/4+y,3/4-x,1/4+z'
  '1/4+z,3/4-y,3/4+x'
  '3/4+z,1/4-y,3/4+x'
  '3/4+z,3/4-y,1/4+x'
  '1/4+x,3/4+y,3/4-z'
  '3/4+x,1/4+y,3/4-z'
  '3/4+x,3/4+y,1/4-z'
  '1/4+y,3/4+z,3/4-x'
  '3/4+y,1/4+z,3/4-x'
  '3/4+y,3/4+z,1/4-x'
  '1/4+z,3/4+x,3/4-y'
  '3/4+z,1/4+x,3/4-y'
  '3/4+z,3/4+x,1/4-y'
  '1/4+x,3/4+z,3/4-y'
  '3/4+x,1/4+z,3/4-y'
  '3/4+x,3/4+z,1/4-y'
  '1/4+y,3/4+x,3/4-z'
  '3/4+y,1/4+x,3/4-z'
  '3/4+y,3/4+x,1/4-z'
  '1/4+z,3/4+y,3/4-x'
  '3/4+z,1/4+y,3/4-x'
  '3/4+z,3/4+y,1/4-x'

loop_
_atom_type_symbol
_atom_type_oxidation_number
  O2-   -2.000
  Al3+   3.000

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
  O1    O2-   32 e 0.37 0.37 0.37 1.  0 d
  Al1   Al3+   8 a 0.25 0.25 0.25 0.503  0 d
  Al2   Al3+  48 f 0.25 0. 0. 0.083  0 d
  Al3   Al3+  16 d 0.625 0.625 0.625 0.564  0 d
  Al4   Al3+  16 c 0.125 0.125 0.125 0.27  0 d

_refine_ls_R_factor_all            0.06