2-Amino-5-nitropyridinium monohydrogenphosphite

The crystal structure of this new 2-amino-5-nitropyridinium salt consists of centrosymmetric double layers built up with C 5 H 6 N 3 O 2 + cations and H 2 PO 3 - phosphite anions. The main feature of this stacking is the presence of centrosymmetric (H 4 P 2 O 6 ) 2- clusters holding both layers together through relatively strong hydrogen bonds. Weaker hydrogen bonds maintain the cohesion of the organic-inorganic arrangement within a layer. Direct bonding exists neither between the organic entities, nor between the double layers. The dimension charge compromise of the anionic group is not favourable for inducing a polar packing of cations which would be necessary to originate nonlinear optical properties