Work

Symmetry Lost, Function Found: A Spectroscopic Perspective on Excited‐State Symmetry Breaking

Year: 2026

Type: article

Abstract: Excited-State Symmetry Breaking (ES-SB) is not an anomaly, it is a natural response of some molecular systems once light drives them out of equilibrium. What is increasingly evident is that symmetry loss offers functional leverage: it dictates charge-localization pathways in chromophores, mediates ion-pair formation in assemblies, and underpins emergent behavior in frameworks and soft semiconductors. This Perspective highlights how advanced ultrafast and Raman-based spectroscopies uncover the structural and environmental coordinates that govern ES-SB and shows how these insights translate into design rules for materials in which controlled asymmetry is advantageous. By viewing ES-SB as an adjustable parameter, rather than a side effect, new strategies emerge for steering photophysics toward improved energy harvesting, directional transport, and responsive functionality.

Source: ChemPhotoChem

DOI: 10.1002/cptc.202500415

Authors: Ryan P. McDonnell, Zachary M. Faitz, Harrison J. Esterly, Giulio Cerullo, Austin B. Gilbert, Tommaso Bianconi

Institutions: University of Wisconsin–Madison, Istituto di Fotonica e Nanotecnologie, National Research Council, Politecnico di Milano

Language: English

Topic: Photochemistry and Electron Transfer Studies

Subfield: Physical and Theoretical Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funder: National Science Foundation Graduate Research Fellowship Program

Award: G4307208066