data_9000028
_publ_section_title
;
 The crystal structure of alpha-SiC, type IV
;
_journal_name_full               'American Mineralogist'
_journal_page_first              431
_journal_page_last               442
_journal_volume                  29
_journal_year                    1944
_chemical_formula_sum            'C7 Si7'
_chemical_name_common            SiC-IV
_space_group_IT_number           160
_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                   3.073
_cell_length_b                   3.073
_cell_length_c                   52.78
_cell_volume                     431.643
_exptl_crystal_density_diffrn    3.239
_[local]_cod_cif_authors_sg_H-M  'R 3 m'
_[local]_cod_chemical_formula_sum_orig 'Si7 C7'
_cod_database_code               9000028
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
-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
Si 0.00000 0.00000 0.00000
Si 0.00000 0.00000 0.19100
Si 0.00000 0.00000 0.28600
Si 0.00000 0.00000 0.42900
Si 0.00000 0.00000 0.57100
Si 0.00000 0.00000 0.71400
Si 0.00000 0.00000 0.81000
C 0.00000 0.00000 0.03600
C 0.00000 0.00000 0.22600
C 0.00000 0.00000 0.32100
C 0.00000 0.00000 0.46400
C 0.00000 0.00000 0.60700
C 0.00000 0.00000 0.75000
C 0.00000 0.00000 0.84500
