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 = 1000 deg C ; _database_code_amcsd 0002805 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'O6 Si2 Mg1.85 Ca.15' _cell_length_a 9.752 _cell_length_b 8.949 _cell_length_c 5.255 _cell_angle_alpha 90 _cell_angle_beta 108.84 _cell_angle_gamma 90 _cell_volume 434.037 _exptl_crystal_density_diffrn 3.109 _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 0.86862 0.33890 0.17197 1.00000 0.02075 O1B 0.37311 0.84175 0.13310 1.00000 0.02136 O2A 0.12226 0.49844 0.33087 1.00000 0.02613 O2B 0.62858 0.98692 0.37344 1.00000 0.03082 O3A 0.10324 0.26674 0.58704 1.00000 0.02842 O3B 0.60230 0.71138 0.48337 1.00000 0.02867 SiA 0.04317 0.34038 0.28182 1.00000 0.01524 SiB 0.54817 0.83878 0.24048 1.00000 0.01576 Mg1 0.25048 0.65186 0.23090 1.00000 0.02196 Mg2 0.25426 0.01793 0.22864 0.85000 0.03481 Ca2 0.25426 0.01793 0.22864 0.15000 0.03481 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 0.01655 0.02735 0.01874 0.00345 0.00625 0.00100 O1B 0.01986 0.02434 0.02009 0.00202 0.00674 0.00018 O2A 0.02956 0.01942 0.03102 -0.00833 0.01199 -0.00410 O2B 0.03185 0.02848 0.03628 -0.01373 0.01675 -0.00999 O3A 0.02092 0.03935 0.02482 0.00030 0.00715 0.01704 O3B 0.02675 0.03591 0.02514 0.00777 0.01085 0.01352 SiA 0.01501 0.01670 0.01515 -0.00186 0.00645 -0.00167 SiB 0.01547 0.01633 0.01619 -0.00176 0.00609 -0.00152 Mg1 0.02398 0.02230 0.01975 -0.00015 0.00728 0.00060 Mg2 0.03785 0.04023 0.02357 0.00768 0.00606 0.00239 Ca2 0.03785 0.04023 0.02357 0.00768 0.00606 0.00239