data_global _amcsd_formula_title 'Cl H4 N O4' loop_ _publ_author_name 'Smith H' 'Levy H' _journal_name_full 'Acta Crystallographica' _journal_volume 15 _journal_year 1962 _journal_page_first 1201 _journal_page_last 1206 _publ_section_title ; Neutron Diffraction Study of Ammonium Perchlorate _cod_database_code 1008111 ; _database_code_amcsd 0016053 _chemical_formula_sum 'N Cl O4' _cell_length_a 9.2 _cell_length_b 5.82 _cell_length_c 7.45 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 398.903 _exptl_crystal_density_diffrn 1.889 _symmetry_space_group_name_H-M 'P n m a' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,z' '-x,1/2+y,-z' '1/2-x,1/2+y,1/2+z' '1/2+x,1/2-y,1/2-z' '1/2+x,y,1/2-z' '1/2-x,-y,1/2+z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z N1 0.18200 0.75000 0.16600 Cl1 0.43200 0.25000 0.19300 O1 0.31400 0.25000 0.06100 O2 0.57000 0.25000 0.10700 O3 0.41800 0.05300 0.30300