data_global
_amcsd_formula_title 'Li.5Al.5Si1.5O4'
loop_
_publ_author_name
'Xu H'
'Heaney P J'
'Beall G H'
_journal_name_full 'American Mineralogist'
_journal_volume 85 
_journal_year 2000
_journal_page_first 971
_journal_page_last 979
_publ_section_title
;
 Phase transitions induced by solid solution in stuffed derivatives of quartz:
 A powder synchrotron XRD study of the LiAlSiO4-SiO2 join
 Sample: x=.50, Li.5Al.5Si1.5O4, beta quartz structure
;
_database_code_amcsd 0002465
_chemical_formula_sum 'Li.25 (Si.75 Al.25) O2'
_cell_length_a 5.1609
_cell_length_b 5.1609
_cell_length_c 5.4574
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 125.883
_exptl_crystal_density_diffrn      2.435
_symmetry_space_group_name_H-M 'P 62 2 2'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,x-y,1/3-z'
  'x-y,x,1/3+z'
  'y,x,2/3-z'
  '-y,x-y,2/3+z'
  '-x+y,y,-z'
  '-x,-y,z'
  '-x,-x+y,1/3-z'
  '-x+y,-x,1/3+z'
  '-y,-x,2/3-z'
  'y,-x+y,2/3+z'
  'x-y,-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
Li   0.00000   0.00000   0.00000   0.25000   0.04400
Si   0.50000   0.00000   0.00000   0.75000   0.01690
Al   0.50000   0.00000   0.00000   0.25000   0.01690
O   0.20520   0.41040   0.50000   1.00000   0.03120