data_global _chemical_name_mineral 'Enstatite' loop_ _publ_author_name 'Yang H' 'Ghose S' _journal_name_full 'Physics and Chemistry of Minerals' _journal_volume 22 _journal_year 1995 _journal_page_first 300 _journal_page_last 310 _publ_section_title ; High temperature single crystal X-ray diffraction studies of the ortho-proto phase transition in enstatite, Mg2Si2O6 at 1360 K Sample: T = 1360 K ; _database_code_amcsd 0007922 _chemical_formula_sum 'Mg Si O3' _cell_length_a 18.456 _cell_length_b 8.960 _cell_length_c 5.270 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 871.478 _exptl_crystal_density_diffrn 3.061 _symmetry_space_group_name_H-M 'P b c a' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' '1/2+x,y,1/2-z' '1/2-x,-y,1/2+z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Mg1 0.37530 0.65100 0.88410 0.03330 Mg2 0.37650 0.48780 0.37910 0.04732 SiA 0.27100 0.33970 0.06420 0.02936 SiB 0.47610 0.33850 0.78420 0.02653 O1A 0.18320 0.34010 0.05640 0.02908 O1B 0.56380 0.34280 0.78590 0.02379 O2A 0.31160 0.49800 0.06260 0.03883 O2B 0.43560 0.48580 0.70050 0.03511 O3A 0.30200 0.22800 -0.16290 0.02940 O3B 0.44990 0.20990 0.57610 0.04017 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 Mg1 0.04314 0.02969 0.02687 0.00251 -0.00345 0.00024 Mg2 0.06902 0.03945 0.03377 -0.00838 -0.00641 0.00502 SiA 0.04487 0.02359 0.02012 0.00168 -0.00049 -0.00383 SiB 0.03796 0.02156 0.02012 0.00335 -0.00246 0.00335 O1A 0.01380 0.04067 0.03222 0.00335 -0.00985 0.00574 O1B 0.00690 0.03538 0.02997 -0.00084 -0.00296 -0.00407 O2A 0.05522 0.02603 0.03503 -0.01257 -0.00443 0.00215 O2B 0.04141 0.03335 0.02997 0.00586 -0.00345 0.00096 O3A 0.00518 0.05735 0.02547 0.00503 0.00493 -0.00718 O3B 0.03279 0.05450 0.03391 -0.00335 0.00148 -0.02368