Articolo in rivista, 2020, ENG, 10.1002/smtd.202000617

Exchange Interactions Drive Supramolecular Chiral Induction in Polyaniline

Mishra, Suryakant; Kumar, Anup; Venkatesan, Munuswamy; Pigani, Laura; Pasquali, Luca; Fontanesi, Claudio

Weizmann Inst Sci; Trinity Coll Dublin; Dept Chem & Geol Sci; Dipartimento Ingn E Ferrari; IOM CNR; Univ Johannesburg

The focus of this paper is on the intermolecular interaction active between polyaniline (PANI) and 10-camphorsulfonic acid (10CSA). Enantiopure 10CSA, present in the electropolymerization solution, promotes chiral induction in the supramolecular polyaniline polymer (cPANI). Tight integration of experimental data (circular dichroism, CD, near edge X-ray absorption spectra, NEXAFS, conductive probe atomic force microscopy, CP-AFM) and theoretical [density functional theory, (DFT)] results allows to unfold the nature of the electronic interaction between PANI and 10CSA and to shed light on the physical interactions inducing the chiral character to bulk pristine non-chiral PANI: eventually yielding cPANI. The electropolymerization follows a "wet chemistry" method: electrochemical polymerization of aniline in the co-presence in bulk solution of enantiopure 10-camphorsulfonic acid (10CSA). The latter is exploited as chirality inductor. The method of integration between experimental results with ab-initio theoretical calculations, strongly suggests that the chiral induction exerted by the CSA stems from exchange interaction between CSA and PANI.

Small methods Online 4 (10)

Keywords

AFM, camphor sulfonic acid, chiral PANI, circular dichroism, density functional theory

CNR authors

Pasquali Luca

CNR institutes