data_1251326 _chemical_formula_sum 'C50 Si50' _symmetry_cell_setting hexagonal _symmetry_space_group_name_H-M 'P 63 m c' _symmetry_Int_Tables_number 186 _cell_length_a 3.08 _cell_length_b 3.08 _cell_length_c 10.081 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 82.82 _cell_formula_units_Z 4 loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_type_symbol _atom_site_occupancy Si 0.333333 0.666667 0.25 Si 0 C 0.333333 0.666667 0.4375 C 0 Si 0 0 0 Si 0 C 0 0 0.1875 C 0