data_9001581
_chemical_name 'Cristobalite'
loop_
_publ_author_name
'Downs R T'
'Palmer D C'
_journal_name_full "American Mineralogist"
_journal_volume 79
_journal_year 1994
_journal_page_first 9
_journal_page_last 14
_publ_section_title
;
 The pressure behavior of alpha cristobalite
 P = 1.05 GPa
;
_chemical_formula_sum 'Si O2'
_cell_length_a 4.8757
_cell_length_b 4.8757
_cell_length_c 6.7163
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 159.663
_symmetry_space_group_name_H-M 'P 41 21 2'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  'y,x,-z'
  '1/2-y,1/2+x,1/4+z'
  '1/2-x,1/2+y,1/4-z'
  '-x,-y,1/2+z'
  '-y,-x,1/2-z'
  '1/2+y,1/2-x,3/4+z'
  '1/2+x,1/2-y,3/4-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_Uiso_or_equiv
Si   0.31250   0.31250   0.00000   0.00646
O   0.23560   0.12690   0.19040   0.01418