2-Amino-5-nitropyridinium acetophosphonate: a deliberately engineered non-linear optical crystal

Abstract

The crystal structure of 2-amino-5-nitropyridinium acetophosphonate confirms the possibility to design at request non-centrosymmetric structures based on the 2-amino-5-nitropyridinium polar chromophore. The non-centrosymmetry in this class of materials is mainly dependent on the structure of the associated counter-anion. Layered anionic aggregates always favour non-centrosymmetrical organization of non-linear cations as evidenced by many crystal structure investigations.