Jahn–Teller-driven electric field response in excited octupolar molecules

Abstract

We present a comprehensive theoretical model to describe the response of an excited octupolar molecule to a static external electric field, explicitly accounting for the critical role of vibronic interactions (Jahn–Teller effect). The key finding is that, regardless of the strength of vibronic interaction, excited octupolar molecules function like qubits with an electric dipole moment. The model unifies the treatment of electronic states and nuclear dynamics and reveals that the field-induced dipole moment and its anisotropy are not intrinsic electronic properties but are profoundly modulated by the coupling to vibrational modes. The temperature dependence of ensemble-averaged dipole moments, bridging the gap between single-molecule properties and bulk experimental observables, is calculated and analyzed. These results provide fundamental insights into the interplay between symmetry, vibronic coupling, and external perturbations in complex molecular systems.