data_9012594
_publ_section_title
;
 Calculated X-ray diffraction data for diamond polytypes
 Note: rhombohedral, 21R structure
 Note: theoretically calculated structure values
;
_journal_name_full               'Journal of the American Ceramic Society'
_journal_page_first              1876
_journal_page_last               1883
_journal_paper_doi               10.1111/j.1151-2916.1992.tb07211.x
_journal_volume                  75
_journal_year                    1992
_chemical_formula_sum            C
_chemical_name_common            Carbon
_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                   2.5221
_cell_length_b                   2.5221
_cell_length_c                   43.2450
_cell_volume                     238.227
_exptl_crystal_density_diffrn    3.516
_[local]_cod_cif_authors_sg_H-M  'R -3 m'
_cod_database_code               9012594
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
C1 0.00000 0.00000 0.01786
C2 0.00000 0.00000 0.17262
C3 0.00000 0.00000 0.20833
C4 0.00000 0.00000 0.26786
C5 0.00000 0.00000 0.30357
C6 0.00000 0.00000 0.41071
C7 0.00000 0.00000 0.44643
