#------------------------------------------------------------------------------
#$Date: 2008-01-26 19:25:03 +0200 (Sat, 26 Jan 2008) $
#$Revision: 20 $
#$URL: file:///home/coder/svn-repositories/cod/cif/1/1000029.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_Yttrium

_chemical_name_systematic          'Yttrium alumosilicate nitrogen oxide *'
_chemical_formula_structural       'Y.5 (Si9.3 Al2.7) (N15.1 O.9)'
_chemical_formula_sum              'Al2.7 N15.1 O.9 Si9.3 Y.5'

_publ_section_title
;
Reitveld refinements for calcium and yttrium containing $-alpha sialons
;
loop_
_publ_author_name
  'Izumi, F'
  'Mitomo, M'
  'Bando, Y'
_journal_name_full                 'Journal of Materials Science'
_journal_coden_ASTM                JMTSAS
_journal_volume                    19
_journal_year                      1984
_journal_page_first                3115
_journal_page_last                 3120

_cell_length_a                     7.82927(7)
_cell_length_b                     7.82927(7)
_cell_length_c                     5.70757(6)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  120
_cell_volume                       303.0
_cell_formula_units_Z              1

_symmetry_space_group_name_H-M     'P 3 1 c'
_symmetry_Int_Tables_number        159
_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-y,-y,1/2+z'
  '-x,y-x,1/2+z'

loop_
_atom_type_symbol
_atom_type_oxidation_number
  Y4+    3.600
  Si4+   4.000
  Al3+   3.000
  N3-   -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
  Y1    Y4+    2 b 0.3333 0.6667 0.242(2) 0.272(2)  0 d
  Si1   Si4+   6 c 0.5087(2) 0.0819(1) 0.213(1) 0.77  0 d
  Al1   Al3+   6 c 0.5087(2) 0.0819(1) 0.213(1) 0.23  0 d
  Si2   Si4+   6 c 0.1706(2) 0.2533(2) 0.002(2) 0.77  0 d
  Al2   Al3+   6 c 0.1706(2) 0.2533(2) 0.002(2) 0.23  0 d
  N1    N3-    2 a 0. 0. 0. 0.94  0 d
  O1    O2-    2 a 0. 0. 0. 0.06  0 d
  N2    N3-    2 b 0.3333 0.6667 0.653(2) 0.94  0 d
  O2    O2-    2 b 0.3333 0.6667 0.653(2) 0.06  0 d
  N3    N3-    6 c 0.3458(3) -0.0472(4) -0.005(2) 0.94  0 d
  O3    O2-    6 c 0.3458(3) -0.0472(4) -0.005(2) 0.06  0 d
  N4    N3-    6 c 0.3219(4) 0.3180(4) 0.246(2) 0.94  0 d
  O4    O2-    6 c 0.3219(4) 0.3180(4) 0.246(2) 0.06  0 d

_refine_ls_R_factor_all            0.059