data_global _chemical_name_mineral 'Beryllium' loop_ _publ_author_name 'Yang Y W' 'Coppens P' _journal_name_full 'Acta Crystallographica, Section A' _journal_volume 34 _journal_year 1978 _journal_page_first 61 _journal_page_last 65 _publ_section_title ; The electron density and bonding in beryllium metal as studied by Fourier methods ; _database_code_amcsd 0009324 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Be' _cell_length_a 2.2858 _cell_length_b 2.2858 _cell_length_c 3.5843 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 16.219 _exptl_crystal_density_diffrn 1.845 _symmetry_space_group_name_H-M 'P 63/m m c' loop_ _space_group_symop_operation_xyz 'x,y,z' '-x,-x+y,1/2+z' 'x,x-y,1/2-z' '-x+y,-x,1/2-z' 'x-y,x,1/2+z' '-y,-x,z' 'y,x,-z' 'y,-x+y,-z' '-y,x-y,z' 'x-y,-y,1/2+z' '-x+y,y,1/2-z' 'x,y,1/2-z' '-x,-y,1/2+z' 'x,x-y,z' '-x,-x+y,-z' 'x-y,x,-z' '-x+y,-x,z' 'y,x,1/2+z' '-y,-x,1/2-z' '-y,x-y,1/2-z' 'y,-x+y,1/2+z' '-x+y,y,z' 'x-y,-y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Be 0.33333 0.66667 0.75000 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 Be 0.00720 0.00720 0.00660 0.00360 0.00000 0.00000