data_global _chemical_name_mineral 'Prosopite' loop_ _publ_author_name 'Pudovkina Z V' 'Chernitsova N M' 'Pyatenko Y A' _journal_name_full 'Journal of Structural Chemistry' _journal_volume 14 _journal_year 1973 _journal_page_first 345 _journal_page_last 347 _publ_section_title ; Refinement of the crystalline structure of prosopite, CaAl2F4(OH)4 ; _database_code_amcsd 0014057 _chemical_formula_sum 'Ca Al2 F4 (O4 H4)' _cell_length_a 6.76 _cell_length_b 11.12 _cell_length_c 7.32 _cell_angle_alpha 90 _cell_angle_beta 95.0 _cell_angle_gamma 90 _cell_volume 548.159 _exptl_crystal_density_diffrn 2.885 _symmetry_space_group_name_H-M 'C 1 2/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '-x,y,1/2-z' '1/2-x,1/2+y,1/2-z' '-x,-y,-z' '1/2-x,1/2-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Ca 0.00000 0.46060 0.25000 0.00849 Al1 0.25000 0.25000 0.00000 0.00722 Al2 0.00000 0.14070 0.25000 0.00697 F1 0.07610 0.38100 0.96250 0.01115 F2 0.18180 0.02440 0.28190 0.01191 O-H1 0.19980 0.26320 0.24390 0.00747 O-H2 0.02310 0.15340 0.99710 0.00811