data_global _chemical_name_mineral 'Phosphammite' loop_ _publ_author_name 'Khan A A' 'Roux J P' 'James W J' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 28 _journal_year 1972 _journal_page_first 2065 _journal_page_last 2069 _publ_section_title ; The crystal structure of diammonium hydrogen phosphate, (NH4)2HPO4 ; _database_code_amcsd 0009438 _chemical_formula_sum 'N2 H9 P O4' _cell_length_a 11.043 _cell_length_b 6.700 _cell_length_c 8.031 _cell_angle_alpha 90 _cell_angle_beta 113.42 _cell_angle_gamma 90 _cell_volume 545.246 _exptl_crystal_density_diffrn 1.609 _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 N1 0.45170 0.11900 0.16080 ? N2 0.12170 0.38570 0.26200 ? H1 0.17900 0.87600 0.13700 0.03926 H2 0.51300 0.16000 0.11500 0.01646 H3 0.41800 0.00000 0.11500 0.01393 H4 0.49600 0.12100 0.28500 0.02280 H5 0.39200 0.20500 0.12700 0.01520 H6 0.17000 0.40500 0.18600 0.02406 H7 0.12500 0.49800 0.31500 0.00633 H8 0.16100 0.29200 0.34800 0.01140 H9 0.04300 0.35100 0.19700 0.01013 P 0.24913 0.89110 0.43043 ? O1 0.20390 0.96780 0.22770 ? O2 0.26440 0.08230 0.53940 ? O3 0.37670 0.77350 0.48450 ? O4 0.13890 0.76020 0.44090 ? loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 N1 0.02601 0.02911 0.03549 0.00103 0.01173 -0.00025 N2 0.02705 0.02251 0.03136 -0.00069 0.00984 -0.00150 P 0.02081 0.01819 0.02146 0.00069 0.00832 -0.00100 O1 0.05098 0.02320 0.02586 0.00103 0.01475 0.00050 O2 0.03329 0.02456 0.03109 -0.00344 0.01438 -0.00575 O3 0.02809 0.03616 0.03742 0.00757 0.01286 -0.00025 O4 0.02549 0.02524 0.03026 -0.00241 0.00870 0.00125