“Direct” measurement of delocalized molecular excitonic wave functions through excitonic and vibronic photon imaging
- Yang Luo
- Gong Chen
- Li Zhang
- Yun-Jie Yu
- Qiu-Shi Meng
- Fan-Fang Kong
- Xiao-Jun Tian
- Yao Zhang
- Yang Zhang
- Zhen-Chao Dong
2026-02-18
Delocalized excitons govern the optoelectronic properties of molecular materials, yet the real-space reconstruction of their wave functions—the spatial distribution of amplitude and phase—has remained a long-standing scientific goal. Here, we demonstrate that scanning tunneling microscopy–induced luminescence enables real-space reconstruction of amplitude and phase of delocalized excitonic states in molecular chains. Through subnanometer-resolved photon imaging of linear molecular chains, coherent purely excitonic (0–0) emission patterns reveal the wave function’s relative phases, while incoherent vibronic (0–1) emission maps the squared wave function amplitudes. This near-field technique enables the reconstruction of wave functions for both bright superradiant states and optically dark subradiant states inaccessible by conventional far-field optics. Furthermore, the submolecular resolution of the vibronic maps allows for the contributions of different vibrational symmetries, namely, Franck-Condon and Herzberg-Teller modes, to be distinguished. Our findings establish a unique approach for the excitonic wave function reconstruction and open a route for exploring exciton dynamics and interactions in molecular systems.