data_nolabel
loop_
_publ_author_name
'Glinnemann, J.'
'King, H. E.'
'Schulz, H.'
'Hahn, T.'
'La Placa, S. J.'
'Dacol, F.'
_publ_section_title
;
 Crystal structures of the low-temperature quartz-type phases of SiO2 and GeO2
 at elevated pressure P = room pressure
;
_journal_name_full               'Zeitschrift fur Kristallographie'
_journal_volume                  198
_journal_page_first              177
_journal_year                    1992
_chemical_formula_sum            SiO2
_chemical_name_common            Quartz
_symmetry_space_group_name_H-M   P3121        # for VESTA use 'P 31 2 1'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_length_a                   4.921
_cell_length_b                   4.921
_cell_length_c                   5.4163
_exptl_crystal_density_diffrn    2.635
loop_
_atom_site_label
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Si  3a  .4698   0     .3333
O   6c  .4151  .2675  .2139
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Si 0.00490 0.00410 0.00460 0.00205 0.00010 0.00020
O  0.01400 0.01020 0.01010 0.00910 0.00290 0.00360
