data_global _chemical_name_mineral 'Baghdadite' loop_ _publ_author_name 'Plaisier J R' 'Jansen J' 'de Graaff R A G' 'Ijdo D J W' _journal_name_full 'Journal of Solid State Chemistry' _journal_volume 115 _journal_year 1995 _journal_page_first 464 _journal_page_last 468 _publ_section_title ; Structure determination of Ca3HfSi2O9 and Ca3ZrSi2O9 from powder diffraction ; _database_code_amcsd 0013849 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Ca3 Zr Si2 O9' _cell_length_a 7.3603 _cell_length_b 10.1766 _cell_length_c 10.4514 _cell_angle_alpha 90 _cell_angle_beta 90.875 _cell_angle_gamma 90 _cell_volume 782.748 _exptl_crystal_density_diffrn 3.493 _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_U_iso_or_equiv Ca1 0.62470 0.80700 0.59940 0.00899 Ca2 0.11980 0.82560 0.58840 0.00899 Ca3 0.63010 0.41930 0.61550 0.00899 Zr 0.12450 0.06290 0.11480 0.00899 Si1 0.83400 0.62400 0.81890 0.00899 Si2 0.40000 0.63500 0.80740 0.00899 O1 0.61760 0.60580 0.77570 0.00899 O2 0.08250 -0.00330 0.75410 0.00899 O3 0.13910 0.37940 0.03100 0.00899 O4 0.10690 0.26340 0.74320 0.00899 O5 0.35570 0.73560 0.22530 0.00899 O6 0.31190 0.49900 0.76030 0.00899 O7 0.37910 0.66360 0.95660 0.00899 O8 0.09760 0.61130 0.50560 0.00899 O9 0.65960 -0.10900 -0.01170 0.00899