Synthesis and characterization of a new organic dihydrogen phosphate–arsenate: [H2(C4H10N2)][H2(As, P)O4]2

Chemical preparation, crystal structure, calorimetric and spectroscopic investigations (IR and RMN) are given for a new non-centrosymmetric organic-cation dihydrogen phosphate-arsenate [H{sub 2}(C{sub 4}H{sub 10}N{sub 2})][H{sub 2}(As, P)O{sub 4}]{sub 2}. This compound is triclinic P1 with the following unit-cell parameters: a = 7.082(2) A, b = 7.796(1) A, c = 12.05(3) A, {alpha} 95.37(2) deg , {beta} = 98.38(3) deg , {gamma} = 62.98(1) deg , Z = 2, V 586.2(1) A{sup 3} and D {sub x} = 1.836 g cm{sup -3}. The crystal structure has been solved and refined to R = 0.03 using 2328 independent reflections. The structure can be described as infinite (H{sub 2}XO) {sub n} chains spreading parallel to the b direction. These chains are themselves interconnected by a set of N-H?O hydrogen bonds generated by the organic entities, alternating with the chains. Solid-state {sup 13}C, {sup 15}N and {sup 31}P MAS NMR spectroscopies are in agreement with the X-ray structure.