Synthesis and characterization of a new organic dihydrogenomonophosphate [3,5-(CH 3O) 2C 6H 3NH 3] 2(H 2PO 4) 2

Abstract

Chemical preparation, crystal structure, calorimetric studies and spectroscopic investigation are given for a new organic cation dihydrogenomonophosphate [3,5-(CH 3O) 2C 6H 3NH 3] 2(H 2PO 4) 2. This compound is triclinic P 1 with the following unit cell parameters: a=9.030(6) Å, b=16.124(5) Å, c=8.868(3) Å, α=75.04(3)°, β=110.71(4)°, γ=104.61(1)°, Z=4, V=1148.0(1) Å 3, Z=2 and ρ cal.=1.454 g cm −3. Crystal structure was solved and refined to R=0.04, 2752 independent reflections. The atomic arrangement can be described as inorganic layers of H 2PO 4 − anions parallel to y= 1 2 planes, between which are located the organic groups. Solid-state 13 C and 31 P MAS-NMR spectroscopies are in agreement with the X-ray structure. Ab initio calculations allow the attribution of the phosphorous and carbon signals to the independent crystallographic sites and to the various atoms of the organic groups.