data_global _chemical_name_mineral 'Virgilite' loop_ _publ_author_name 'Li C T' _journal_name_full 'Zeitschrift fur Kristallographie' _journal_volume 127 _journal_year 1968 _journal_page_first 327 _journal_page_last 348 _publ_section_title ; The crystal structure of LiAlSi2O6 III (high-quartz solid solution) ; _database_code_amcsd 0010668 _chemical_formula_sum 'Li.333 (Al.333 Si.667) O2' _cell_length_a 5.217 _cell_length_b 5.217 _cell_length_c 5.464 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 128.790 _exptl_crystal_density_diffrn 2.399 _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 Li 0.00000 0.00000 0.00000 0.33330 Al 0.50000 0.00000 0.00000 0.33330 Si 0.50000 0.00000 0.00000 0.66670 O 0.20570 0.41140 0.50000 1.00000 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 0.00476 0.01065 0.07714 0.00538 0.00000 0.00000 Al 0.00434 0.00290 0.00272 0.00145 0.00000 0.00000 Si 0.00434 0.00290 0.00272 0.00145 0.00000 0.00000 O 0.01820 0.01944 0.02813 0.00972 0.01113 0.00000