Chiral inversion and nonlinear optical response of pseudo[7]catenane-type pillar[8]arene derivatives: Solvent effects and physical mechanisms

Abstract

This study employs density functional theory (DFT) and wavefunction analysis to elucidate the solvent-driven chiral inversion mechanism in molecular universal joint 3 (MUJ3). Key parameters were quantified via the SMD model, revealing a nonlinear correlation with optical responses. UV–Vis spectra exhibited significant solvent-induced red-shifts ($\Delta \lambda$_max up to 20 nm), attributed to enhanced electron localization and suppressed charge transfer (CT) via transition density matrix (TDM) and charge density difference (CDD) analyses. Notably, formamide and 1,2-DiBromoEthane maximized two-photon absorption cross-sections ($\sigma$_TPA $\approx$ 118 GM) through synergistic modulation of transition dipole moments. These findings provide strategies for manipulating supramolecular chiroptics.