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 = 296 K ; _database_code_amcsd 0007919 _chemical_formula_sum 'Mg Si O3' _cell_length_a 18.251 _cell_length_b 8.814 _cell_length_c 5.181 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 833.438 _exptl_crystal_density_diffrn 3.200 _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 0.37580 0.65370 0.86600 0.00536 Mg2 0.37680 0.48690 0.35900 0.00766 SiA 0.27170 0.34150 0.05050 0.00418 SiB 0.47350 0.33740 0.79830 0.00405 O1A 0.18340 0.34000 0.03560 0.00586 O1B 0.56250 0.34030 0.80020 0.00581 O2A 0.31080 0.50270 0.04320 0.00686 O2B 0.43270 0.48330 0.68960 0.00669 O3A 0.30320 0.22260 -0.16790 0.00676 O3B 0.44750 0.19550 0.60400 0.00648 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 0.00675 0.00590 0.00422 0.00000 -0.00096 0.00046 Mg2 0.00844 0.00866 0.00612 -0.00081 -0.00144 0.00046 SiA 0.00506 0.00472 0.00340 0.00000 0.00000 -0.00046 SiB 0.00337 0.00433 0.00367 0.00000 -0.00048 0.00023 O1A 0.00506 0.00748 0.00530 0.00000 0.00048 -0.00023 O1B 0.00506 0.00748 0.00585 0.00081 0.00000 0.00023 O2A 0.00844 0.00551 0.00707 -0.00163 0.00000 -0.00023 O2B 0.00844 0.00630 0.00476 0.00163 -0.00048 0.00116 O3A 0.00675 0.00945 0.00435 0.00000 0.00000 -0.00231 O3B 0.00675 0.00748 0.00503 -0.00081 0.00048 -0.00139