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 = 650 deg C ; _database_code_amcsd 0002803 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'O6 Si2 Mg1.85 Ca.15' _cell_length_a 9.713 _cell_length_b 8.913 _cell_length_c 5.234 _cell_angle_alpha 90 _cell_angle_beta 108.64 _cell_angle_gamma 90 _cell_volume 429.350 _exptl_crystal_density_diffrn 3.143 _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 0.86807 0.33954 0.17543 1.00000 0.01717 O1B 0.37321 0.84096 0.13015 1.00000 0.01491 O2A 0.12149 0.49930 0.32662 1.00000 0.02036 O2B 0.63021 0.98629 0.37674 1.00000 0.02326 O3A 0.10371 0.27021 0.59168 1.00000 0.02110 O3B 0.60314 0.70639 0.47337 1.00000 0.01973 SiA 0.04250 0.34052 0.28366 1.00000 0.01172 SiB 0.54963 0.83857 0.23700 1.00000 0.01133 Mg1 0.25025 0.65276 0.22705 1.00000 0.01589 Mg2 0.25478 0.01793 0.22547 0.85000 0.02602 Ca2 0.25478 0.01793 0.22547 0.15000 0.02602 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 0.01259 0.02205 0.01565 -0.00213 0.00282 -0.00038 O1B 0.01344 0.01662 0.01427 0.00024 0.00386 -0.00023 O2A 0.02458 0.01618 0.02138 -0.00751 0.00883 -0.00333 O2B 0.02393 0.01912 0.02850 -0.00742 0.01085 -0.00684 O3A 0.01794 0.02438 0.02033 -0.00114 0.00521 0.00996 O3B 0.01803 0.02328 0.01792 0.00399 0.00582 0.00860 SiA 0.01182 0.01240 0.01091 -0.00126 0.00359 -0.00098 SiB 0.01181 0.01040 0.01178 -0.00170 0.00377 -0.00118 Mg1 0.01807 0.01629 0.01330 0.00098 0.00501 0.00100 Mg2 0.02634 0.03240 0.01676 0.00475 0.00326 0.00277 Ca2 0.02634 0.03240 0.01676 0.00475 0.00326 0.00277