Synthesis and characterization of a new p-phenylenediammonium dihydrogenmonophosphate [p-NH_3C_6H_4NH_3][H_2PO_4]_2

摘要

Chemical preparation, crystal structure and NMR spectroscopy of a new organic cation p-phenylenediammonium monopho-sphate [p-NH_3C_6H_4NH_3][H_2PO_4]_2 are presented. This new compound crystallizes in the orthorhombic system, with the space group Pnma and the following parameters: a = 7.970 (2) A; b = 22.770 (7) A; c = 7.000 (7) A, V= 1270.3 (11) A~3, Z = 4 and D_x = 1.590 g cm~(-3). The crystal structure has been determined and refiped to R = 0.043 and R_((w)) = 0.057 using 2623 independent reflections. The structural arrangement can be described as inorganic layers of (H_8P_4O_(16))~(4-) units, parallel to (a, c) planes. The organic groups (p-H_3NC_6H_4NH_3)~(2+)are anchored between the phosphoric layers to form a three-dimensional infinite network. This compound is also investigated by IR and solid-state ~1H, ~(13)C and ~(31)P MAS NMR spectroscopies. The ab initio method is used in the calculation of chemical shifts.