data_global _chemical_name_mineral 'Virgilite' loop_ _publ_author_name 'Muller G' 'Paulus H' 'Stiefel J' _journal_name_full 'Neues Jahrbuch fur Mineralogie, Monatshefte' _journal_volume 1990 _journal_year 1990 _journal_page_first 493 _journal_page_last 503 _publ_section_title ; Synthesis and structure of beta-quartz type Na0.5H0.5AlSi206 as compared to LiAlSi206 Note: stuffed beta-quartz type structure ; _database_code_amcsd 0014849 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Li.333 (Al.333 Si.667) O2' _cell_length_a 5.226 _cell_length_b 5.226 _cell_length_c 5.465 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 129.259 _exptl_crystal_density_diffrn 2.391 _symmetry_space_group_name_H-M 'P 62 2 2' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,x-y,1/3-z' 'x-y,x,1/3+z' 'y,x,2/3-z' '-y,x-y,2/3+z' '-x+y,y,-z' '-x,-y,z' '-x,-x+y,1/3-z' '-x+y,-x,1/3+z' '-y,-x,2/3-z' 'y,-x+y,2/3+z' 'x-y,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy _atom_site_U_iso_or_equiv Li 0.00000 0.00000 0.00000 0.33333 0.03306 Al 0.50000 0.00000 0.00000 0.33333 0.01102 Si 0.50000 0.00000 0.00000 0.66667 0.01102 O 0.20300 0.40600 0.50000 1.00000 0.02938 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 Li 0.01200 0.02100 0.07000 0.01100 0.00000 0.00000 Al 0.01100 0.00980 0.01170 0.00490 0.00000 0.00000 Si 0.01100 0.00980 0.01170 0.00490 0.00000 0.00000 O 0.02700 0.02790 0.03380 0.01400 0.01300 0.00000