Work

Theoretical-computational modeling of the vibrational chirality of interacting chromophores: VCD signal and equilibrium properties of excitonic clusters

Year: 2026

Type: article

Abstract: In this work, we extend the perturbed matrix method combined with molecular dynamics simulations, to the modeling of Vibrational Circular Dichroism (VCD) spectra, including non-covalent excitonic coupling among distinct molecular chromophores. The method is applied to (R)-propylene oxide as a benchmark system, comparing infinite-dilution conditions with highly concentrated solutions in water and carbon tetrachloride. The calculated VCD spectra show very good agreement with experimental data and only weak concentration dependence. However, analysis of the excitonic eigenstates reveals the formation of transient, thermally populated excitonic clusters characterized by delocalized vibrational excitations and widely dispersed rotatory strengths. The equilibrium distribution and free-energy profile of these clusters are characterized, providing microscopic insights into excitonic effects in VCD spectra of soft condensed-phase systems.

Source: The Journal of Chemical Physics

DOI: 10.1063/5.0326643

Authors: Andrea Amadei, Massimiliano Aschi

Institutions: University of Rome Tor Vergata, University of L'Aquila

Language: English

Topic: Molecular spectroscopy and chirality

Subfield: Spectroscopy

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,500

Funder: Ministero dell'Università e della Ricerca