Saikat Kumar Seth
Jadavpur University, India
Title: Salt-bridge (SB) interaction at work in building extended supramolecular networks: Experimental and theoretical study
Biography
Biography: Saikat Kumar Seth
Abstract
A series of pyridinium-carboxylate salts were designed prepared and structurally characterized to explore the importance of salt-bridge (SB) interactions in building self-assembled structures. We present a comprehensive analysis of the SB interaction in crystal structures of 4, 4′-Oxybis (benzoic acid) with substituted aminopyridines where the SBs displays extremely well defined geometric preferences. In the solid-state, compound exhibit lone-pair (l.p) ··· (SB)/(SB)···π+ assemblies while compound shows C‒H···(SB)/(SB)···π network. Interestingly, compound exhibit two distinct networks π+···(SB)/(SB)···(SB)/(SB)···π+ and C‒H···(SB)/(SB)···H‒C. These unexplored extended supramolecular networks are evident and explored for the first time in crystal structures. Our study also describes the duality of the salt bridge in establishing π-facial interactions with electron rich and/or electron poor moieties depending on the positive or negative nature of the SB counterpart that interacts with the SB surface. We describe the energetic and geometric features of salt-bridge interaction and explore its impact on the resultant supramolecular organization using high-level theoretical DFT-D3 calculations. The theoretical study combines the energetic features of the noncovalent forces that participate in the extended network and the characterization of the diverse interactions by means of Bader’s theory of ‘‘atoms in molecules’’.
