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 = 500 K ; _database_code_amcsd 0007509 _chemical_formula_sum 'Ca Ti Si O5' _cell_length_a 7.0719 _cell_length_b 8.7464 _cell_length_c 6.5783 _cell_angle_alpha 90 _cell_angle_beta 113.751 _cell_angle_gamma 90 _cell_volume 372.430 _exptl_crystal_density_diffrn 3.496 _symmetry_space_group_name_H-M 'A 1 2/a 1' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2+y,1/2+z' '1/2+x,-y,z' '1/2+x,1/2-y,1/2+z' '1/2-x,y,-z' '1/2-x,1/2+y,1/2-z' '-x,-y,-z' '-x,1/2-y,1/2-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Ca 0.25000 0.66890 0.50000 Ti 0.50000 0.50000 0.00000 Si 0.75000 0.68270 0.50000 O1 0.75000 0.57030 0.00000 O2A 0.91130 0.56580 0.68570 O3A 0.38290 0.71080 0.89740 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 0.03861 0.01229 0.01546 0.00000 0.00077 0.00000 Ti 0.02161 0.01256 0.01005 0.00258 0.00381 -0.00125 Si 0.01161 0.00636 0.00512 0.00000 0.00182 0.00000 O1 0.01002 0.01167 0.02057 0.00000 0.00703 0.00000 O2A 0.02014 0.01535 0.01113 0.00267 0.00434 0.00053 O3A 0.01713 0.01062 0.01409 0.00275 0.00721 0.00323