data_9013921
_publ_section_title
;
 High-pressure polymorphism of the copper(I) halides:
 A neutron-diffraction study to ~10 GPa
 Note: P = 1.74 GPa
 Note: known as CuI-IV
;
_journal_name_full               'Physical Review B'
_journal_page_first              5868
_journal_page_last               5885
_journal_paper_doi               10.1103/PhysRevB.50.5868
_journal_volume                  50
_journal_year                    1994
_chemical_formula_sum            'Cu I'
_chemical_name_mineral           Marshite
_space_group_IT_number           166
_symmetry_space_group_name_Hall  '-R 3 2"'
_symmetry_space_group_name_H-M   'R -3 m :H'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_length_a                   4.155
_cell_length_b                   4.155
_cell_length_c                   20.48
_cell_volume                     306.198
_diffrn_ambient_pressure         1.74e+06
_exptl_crystal_density_diffrn    6.197
_[local]_cod_cif_authors_sg_H-M  'R -3 m'
_cod_database_code               9013921
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
2/3+x,1/3+y,1/3+z
1/3+x,2/3+y,2/3+z
x,x-y,z
2/3+x,1/3+x-y,1/3+z
1/3+x,2/3+x-y,2/3+z
y,x,-z
2/3+y,1/3+x,1/3-z
1/3+y,2/3+x,2/3-z
-x+y,y,z
2/3-x+y,1/3+y,1/3+z
1/3-x+y,2/3+y,2/3+z
-x,-x+y,-z
2/3-x,1/3-x+y,1/3-z
1/3-x,2/3-x+y,2/3-z
-y,-x,z
2/3-y,1/3-x,1/3+z
1/3-y,2/3-x,2/3+z
x-y,-y,-z
2/3+x-y,1/3-y,1/3-z
1/3+x-y,2/3-y,2/3-z
y,-x+y,-z
2/3+y,1/3-x+y,1/3-z
1/3+y,2/3-x+y,2/3-z
-x+y,-x,z
2/3-x+y,1/3-x,1/3+z
1/3-x+y,2/3-x,2/3+z
-x,-y,-z
2/3-x,1/3-y,1/3-z
1/3-x,2/3-y,2/3-z
-y,x-y,z
2/3-y,1/3+x-y,1/3+z
1/3-y,2/3+x-y,2/3+z
x-y,x,-z
2/3+x-y,1/3+x,1/3-z
1/3+x-y,2/3+x,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
Cu 0.00000 0.00000 0.12930 0.04433
I1 0.00000 0.00000 0.00000 0.01900
I2 0.00000 0.00000 0.50000 0.01900
