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 = 440 K ; _database_code_amcsd 0007507 _chemical_formula_sum 'Ca Ti Si O5' _cell_length_a 7.0701 _cell_length_b 8.7405 _cell_length_c 6.5747 _cell_angle_alpha 90 _cell_angle_beta 113.773 _cell_angle_gamma 90 _cell_volume 371.818 _exptl_crystal_density_diffrn 3.502 _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 0.24680 0.41870 0.25350 Ti 0.50610 0.25110 0.75090 Si 0.75040 0.43260 0.24910 O1 0.74670 0.32040 0.74500 O2A 0.91180 0.31750 0.43510 O2B 0.09010 0.18490 0.06600 O3A 0.38160 0.45910 0.64580 O3B 0.61700 0.03850 0.85170 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 0.03183 0.00863 0.00917 0.00481 -0.00112 -0.00008 Ti 0.01516 0.00937 0.00699 0.00278 0.00207 0.00005 Si 0.00732 0.00507 0.00409 -0.00530 0.00146 -0.00083 O1 0.01058 0.01018 0.01924 -0.00304 0.00815 -0.00421 O2A 0.01516 0.01362 0.00801 0.00069 0.00114 -0.00258 O2B 0.01597 0.01366 0.01148 0.00341 0.00507 0.00541 O3A 0.01285 0.01149 0.01280 0.00100 0.00602 0.00048 O3B 0.01555 0.00612 0.00978 0.00395 0.00531 0.00330