data_global _amcsd_formula_title 'NH4AlF4' loop_ _publ_author_name 'Bulou A' 'Leble A' 'Hewat A' _journal_name_full 'Materials Research Bulletin' _journal_volume 17 _journal_year 1982 _journal_page_first 391 _journal_page_last 397 _publ_section_title ; NH4AlF4: Determination of the Ordered and Disordered Structures by Neutron Powder Profile Refinement _cod_database_code 1000182 ; _database_code_amcsd 0014295 _chemical_formula_sum 'N H4 Al F4' _cell_length_a 5.0875 _cell_length_b 5.0875 _cell_length_c 12.7319 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 329.535 _exptl_crystal_density_diffrn 2.439 _symmetry_space_group_name_H-M 'I 4/m c m' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,1/2+z' '-y,-x,1/2+z' '1/2-y,1/2-x,+z' 'y,x,1/2-z' '1/2+y,1/2+x,-z' 'y,-x,-z' '1/2+y,1/2-x,1/2-z' '-y,x,z' '1/2-y,1/2+x,1/2+z' 'x,-y,1/2+z' '1/2+x,1/2-y,+z' '-x,y,1/2-z' '1/2-x,1/2+y,-z' 'x,y,-z' '1/2+x,1/2+y,1/2-z' '-x,-y,z' '1/2-x,1/2-y,1/2+z' 'y,x,1/2+z' '1/2+y,1/2+x,+z' '-y,-x,1/2-z' '1/2-y,1/2-x,-z' '-y,x,-z' '1/2-y,1/2+x,1/2-z' 'y,-x,z' '1/2+y,1/2-x,1/2+z' '-x,y,1/2+z' '1/2-x,1/2+y,+z' 'x,-y,1/2-z' '1/2+x,1/2-y,-z' '-x,-y,-z' '1/2-x,1/2-y,1/2-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy N1 0.00000 0.50000 0.25000 1.00000 H1 -0.00150 0.33030 0.20430 0.50000 Al1 0.00000 0.00000 0.00000 1.00000 F1 0.00000 0.00000 0.13860 1.00000 F2 0.21020 0.71020 0.00000 1.00000