data_global _chemical_name_mineral 'Titanite' loop_ _publ_author_name 'Ghose S' 'Ito Y' 'Hatch D M' _journal_name_full 'Physics and Chemistry of Minerals' _journal_volume 17 _journal_year 1991 _journal_page_first 591 _journal_page_last 603 _publ_section_title ; Paraelectric-antiferroelectric phase transition in titanite, CaTiSiO5 I. A high temperature X-ray diffraction study of the order parameter and transition mechanism Sample: T = 450 K ; _database_code_amcsd 0007508 _chemical_formula_sum 'Ca Ti Si O5' _cell_length_a 7.0706 _cell_length_b 8.7416 _cell_length_c 6.5751 _cell_angle_alpha 90 _cell_angle_beta 113.768 _cell_angle_gamma 90 _cell_volume 371.928 _exptl_crystal_density_diffrn 3.501 _symmetry_space_group_name_H-M 'P 1 21/a 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2-y,z' '1/2-x,1/2+y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Ca 0.24320 0.41860 0.25090 Ti 0.50120 0.25150 0.75030 Si 0.75090 0.43280 0.25110 O1 0.74860 0.32100 0.75070 O2A 0.91120 0.31550 0.43660 O2B 0.08890 0.18340 0.06590 O3A 0.38370 0.46000 0.64710 O3B 0.61850 0.03910 0.85310 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 Ca 0.03086 0.00871 0.01091 0.00648 -0.00061 0.00480 Ti 0.01625 0.00890 0.00737 0.00295 0.00223 0.00000 Si 0.00651 0.00499 0.00460 0.00226 0.00097 0.00099 O1 0.01056 0.01103 0.01772 0.00857 0.00661 -0.00013 O2A 0.01421 0.01870 0.00341 -0.00192 -0.00462 0.00035 O2B 0.01856 0.00910 0.01205 0.00613 0.00903 0.00192 O3A 0.00980 0.00205 0.01952 -0.00364 0.00915 0.00991 O3B 0.01727 0.01932 0.00682 0.00994 0.00357 0.01527