data_global _chemical_name_mineral 'Clinoenstatite' loop_ _publ_author_name 'Tribaudino M' 'Nestola F' 'Camara F' 'Domeneghetti M C' _journal_name_full 'American Mineralogist' _journal_volume 87 _journal_year 2002 _journal_page_first 648 _journal_page_last 657 _publ_section_title ; The high-temperature P2_1/c - C2/c phase transition in Fe-free pyroxene (Ca.15Mg1.85Si2O6): Structural and thermodynamic behavior Sample: dien2, T = 800 deg C ; _database_code_amcsd 0002804 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'O6 Si2 Mg1.85 Ca.15' _cell_length_a 9.739 _cell_length_b 8.936 _cell_length_c 5.249 _cell_angle_alpha 90 _cell_angle_beta 108.80 _cell_angle_gamma 90 _cell_volume 432.437 _exptl_crystal_density_diffrn 3.120 _symmetry_space_group_name_H-M 'P 1 21/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-x,1/2+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_occupancy _atom_site_U_iso_or_equiv O1A 0.86828 0.33961 0.17249 1.00000 0.01942 O1B 0.37346 0.84123 0.13248 1.00000 0.01912 O2A 0.12164 0.49858 0.32875 1.00000 0.02349 O2B 0.62975 0.98637 0.37552 1.00000 0.02678 O3A 0.10313 0.26764 0.58800 1.00000 0.02651 O3B 0.60222 0.70925 0.47905 1.00000 0.02480 SiA 0.04294 0.34079 0.28246 1.00000 0.01375 SiB 0.54865 0.83882 0.23917 1.00000 0.01385 Mg1 0.25051 0.65217 0.22924 1.00000 0.02020 Mg2 0.25431 0.01745 0.22774 0.85000 0.03230 Ca2 0.25431 0.01745 0.22774 0.15000 0.03230 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 O1A 0.01595 0.02406 0.01797 0.00094 0.00505 0.00149 O1B 0.01476 0.02284 0.01853 0.00146 0.00368 -0.00057 O2A 0.02631 0.01887 0.02612 -0.00863 0.00961 -0.00341 O2B 0.03137 0.02224 0.02992 -0.00943 0.01431 -0.00841 O3A 0.02048 0.03486 0.02415 -0.00056 0.00716 0.01199 O3B 0.02226 0.03067 0.02337 0.00350 0.00998 0.01248 SiA 0.01284 0.01520 0.01384 -0.00107 0.00518 -0.00056 SiB 0.01469 0.01415 0.01394 -0.00138 0.00632 -0.00078 Mg1 0.02213 0.02058 0.01778 0.00014 0.00625 0.00025 Mg2 0.03421 0.03803 0.02157 0.00622 0.00470 0.00261 Ca2 0.03421 0.03803 0.02157 0.00622 0.00470 0.00261