data_9012605
_publ_section_title
;
 High-pressure crystal chemistry and amorphization of alpha-quartz
 Locality: synthetic
 Sample: P = 12.5 GPa
;
_journal_name_full               'Solid State Communications'
_journal_page_first              507
_journal_page_last               511
_journal_paper_doi               10.1016/0038-1098(89)90607-8
_journal_volume                  72
_journal_year                    1989
_chemical_formula_sum            'O2 Si'
_chemical_name_mineral           Quartz
_space_group_IT_number           152
_symmetry_space_group_name_Hall  'P 31 2"'
_symmetry_space_group_name_H-M   'P 31 2 1'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_length_a                   4.535
_cell_length_b                   4.535
_cell_length_c                   5.170
_cell_volume                     92.082
_diffrn_ambient_pressure         1.25e+07
_exptl_crystal_density_diffrn    3.251
_[local]_cod_chemical_formula_sum_orig 'Si O2'
_cod_database_code               9012605
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
y,x,-z
-y,x-y,1/3+z
-x,-x+y,1/3-z
-x+y,-x,2/3+z
x-y,-y,2/3-z
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Si 0.44870 0.00000 0.33333 0.00646
O 0.36700 0.29520 0.24270 0.01089
