data_global _chemical_name_mineral 'Tridymite' loop_ _publ_author_name 'Kato V K' 'Nukui A' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 32 _journal_year 1976 _journal_page_first 2486 _journal_page_last 2491 _publ_section_title ; Die kristallstruktur des monoklinen tief-tridymits ; _database_code_amcsd 0020734 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Si O2' _cell_length_a 18.494 _cell_length_b 4.991 _cell_length_c 25.832 _cell_angle_alpha 90 _cell_angle_beta 117.75 _cell_angle_gamma 90 _cell_volume 2110.152 _exptl_crystal_density_diffrn 2.270 _symmetry_space_group_name_H-M 'C 1 c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Si1 0.02000 0.18960 0.03800 Si2 0.20670 0.28990 0.09691 Si3 0.03490 0.70460 0.20212 Si4 0.22280 0.80460 0.26187 Si5 0.05380 0.19920 0.37631 Si6 0.24270 0.20590 0.43476 Si7 0.26800 0.78480 0.06278 Si8 0.45510 0.70400 0.12843 Si9 0.29290 0.30060 0.23294 SilO 0.48370 0.19940 0.30132 Si11 0.29910 0.71300 0.39594 Si12 0.48340 0.80830 0.46057 O1 0.00360 -0.10650 0.01410 O2 -0.00640 0.39290 -0.01580 O3 -0.03120 0.25190 0.07260 O4 -0.02180 -0.09430 0.15130 O5 0.01250 0.40460 0.18000 O6 0.02360 0.74980 0.25950 O7 0.02530 -0.09510 0.35560 O8 -0.00060 0.40270 0.32470 O9 0.04510 0.25770 0.43490 O10 0.11660 0.23230 0.08390 O11 0.12940 0.75540 0.21970 O12 0.14820 0.22800 0.39210 O13 0.23520 0.08520 0.06190 O14 0.21220 0.58700 0.07710 O15 0.26640 0.24910 0.16670 O16 0.24760 0.10220 0.25680 O17 0.27400 0.59750 0.24310 O18 0.24290 0.75010 0.32880 O19 0.27220 -0.08320 0.43280 O20 0.29140 0.41350 0.41400 O21 0.26290 0.27270 0.50080 O22 0.36310 0.75640 0.11190 O23 0.38870 0.25210 0.26910 O24 0.39220 0.76320 0.40920 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 Si1 0.01167 0.00909 0.01086 -0.00124 0.00739 0.00289 Si2 0.01167 0.01262 0.00821 0.00000 0.00493 -0.00058 Si3 0.01045 0.01098 0.00715 -0.00166 0.00341 0.00058 Si4 0.01154 0.00871 0.00874 0.00124 0.00436 0.00116 Si5 0.00909 0.01047 0.00953 -0.00083 0.00436 -0.00058 Si6 0.00841 0.01123 0.01006 0.00083 0.00626 0.00520 Si7 0.01099 0.00972 0.00927 0.00248 0.00626 -0.00405 Si8 0.00896 0.01211 0.00980 0.00248 0.00398 0.00289 Si9 0.00597 0.01237 0.00900 0.00166 0.00133 0.00058 SilO 0.00923 0.00972 0.00900 0.00083 0.00341 0.00173 Si11 0.00814 0.01010 0.00768 -0.00083 0.00379 0.00289 Si12 0.01045 0.01047 0.00953 0.00041 0.00550 -0.00347 O1 0.03528 0.01275 0.01006 -0.00207 0.00739 -0.00347 O2 0.03393 0.00732 0.02595 0.00000 0.02009 0.00058 O3 0.02036 0.05818 0.01324 0.00248 0.01251 0.00751 O4 0.01900 0.00732 0.02621 -0.00248 0.00644 0.00462 O5 0.02986 0.02309 0.01430 -0.00207 0.00265 -0.00058 O6 0.03257 0.04392 0.01827 -0.00993 0.01706 -0.00751 O7 0.03393 0.01312 0.01562 -0.00786 0.01137 -0.00983 O8 0.02036 0.00644 0.02515 -0.00207 0.00095 -0.00116 O9 0.01221 0.01943 0.01642 -0.00248 0.00872 -0.00809 O10 0.00950 0.02145 0.01933 -0.00041 0.00398 0.00636 O11 0.01221 0.12935 0.01006 -0.00952 0.00265 0.00173 O12 0.00679 0.12695 0.01244 0.00331 0.00322 0.00462 O13 0.02714 0.01237 0.01668 0.00786 0.01213 0.00116 O14 0.01900 0.01514 0.02012 0.00248 0.01251 0.00636 O15 0.01900 0.00252 0.01112 -0.00124 0.00379 0.00000 O16 0.04071 0.01439 0.02780 -0.00869 0.02578 -0.00578 O17 0.02443 0.01199 0.04475 0.00083 0.02426 0.00000 O18 0.02443 0.19308 0.00821 0.00621 0.00720 0.02486 O19 0.02986 0.01249 0.02542 0.00331 0.01687 0.00289 O20 0.02036 0.00681 0.01642 -0.00372 0.01251 0.00000 O21 0.01900 0.01943 0.00821 -0.00786 0.00872 -0.00116 O22 0.00814 0.01350 0.01377 0.00331 0.00550 0.00231 O23 0.00543 0.04038 0.02807 0.00497 -0.00246 -0.00636 O24 0.01086 0.06726 0.01959 -0.01117 0.00815 0.00058