Crystal Structure and Spectroscopic Studies of a New Organic Dihydrogenmonophosphate [2-NH2-6-CH3-C4H3N2O]2(H2PO4)2.

Physicochemical properties of a new dihydrogenmonophosphate [2-NH2-6-CH3-C4H3N2O]2(H2PO4)2 are described on the basis of X-ray crystal structure investigation. This compound crystallizes in the triclinic space group P-1. The unit cell parameters are: a = 7.667(3) Å, b = 8.204(5) Å, c = 14.761(6) Å, α = 98.85(4)°, β = 99.23(3)°, γ = 90.50(4)°, V = 905.0 Å3, and Z = 2. The crystal structure was solved and refined to R = 0.037, using 4351 independent reflections. The atomic arrangement of this compound is built up by (H2PO4)nn - chains. Each chain aggregates with organic molecules to form an open framework architecture through hydrogen bond interactions. The structure includes four types of hydrogen bonds. The first one, O─H─O, links the H2PO4 groups to form (H2PO4)nn - infinite inorganic chains parallel to the a axis. The three other types, O─H─O(carbonylic), N─H─O(carbonylic), and N─H─O, assemble the inorganic chains so as to build up a three-dimensional arrangement. This compound has also been investigated by IR, and solid-state 13C and 31P MAS NMR spectroscopies combined to ab initio calculations. [ABSTRACT FROM AUTHOR]