Theoretical prediction for monitoring Jahn-Teller vibrational evolution using real-space tip-enhanced Raman imaging

The Jahn-Teller effect (JTE) reduces the geometrical symmetry of a system with degenerate electronic states via vibronic coupling, playing a pivotal role in molecular and condensed systems. However, due to the intrinsic limitations of conventional techniques, only the electronic evolution in JTE can be measured. Herein, we theoretically propose that vibrational resolved tip-enhanced Raman scattering images can visualize the vibrational evolutions in JTE in real space. Taking an experimentally accessible single zinc phthalocyanine (ZnPc) molecule as a proof-of-principle example, not only the degenerate vibrational splitting but also the overlooked vibration mixing caused by the JTE in its anionic form can be characterized by Raman images. Leveraging Raman images, the controllable configuration of JTE distortion with partial isotopic substitution can be further identified. These findings establish a practical protocol to monitor the detailed vibrational evolutions when a single molecule experiences JTE, providing a pathway for visualization of spontaneous symmetry breaking in molecular and solid-state systems.