data_global _chemical_name_mineral 'Prosopite' loop_ _publ_author_name 'Pudovkina Z V' 'Pyatenko Y A' _journal_name_full 'Doklady Akademii Nauk SSSR' _journal_volume 190 _journal_year 1970 _journal_page_first 665 _journal_page_last 667 _publ_section_title ; About the structure of the prosopite, Ca[Al2F4(OH)4], and about some features of the fluoroaluminate crystal chemistry ; _database_code_amcsd 0012448 _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 95.00 _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 0.46100 0.25000 0.00785 AlI 0.25000 0.25000 0.00000 0.00785 AlII 0.00000 0.14300 0.25000 0.00785 FI 0.07700 0.38200 0.96500 0.00785 FII 0.18200 0.02100 0.28500 0.00785 O-HI 0.20100 0.26400 0.25700 0.00785 O-HII 0.02300 0.15000 0.99700 0.00785