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Enhanced Quantum-Confined Stark Effect in Sc3N@Ih-C80 Fullerene Dimers Via Intermolecular Coupling
Shaohua Wei1, Xiaowei Yang2, Yang Zhao3
1Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian116024, China.
The Journal of Physical Chemistry Letters
|July 22, 2026
Summary
External electric fields tune molecular excited states and luminescence. Covalent bridging in Sc3N@Ih-C80 dimers enhances this tunability, guiding the design of molecular optoelectronic devices.
Area of Science:
- * Molecular physics and quantum chemistry.
- * Materials science and nanotechnology.
Background:
- * External electric fields can modulate molecular excited states and luminescence.
- * Tunable optical and quantum devices require fundamental physical understanding at the molecular scale.
Purpose of the Study:
- * To investigate the electric-field response of the quantum-confined Stark effect (QCSE).
- * To explore the impact of covalent bridging on electric-field tunability in endohedral metallofullerene dimers.
Main Methods:
- * Density functional theory (DFT) calculations.
- * Time-dependent density functional theory (TDDFT) calculations.
Main Results:
- * Covalent bridging significantly enhances electric-field tunability of energy levels compared to monomers.
- * Low-to-moderate fields are governed by polarizability; stronger fields induce electron-hole separation and exciton evolution.
- * Exciton evolution shifts from Frenkel to charge-transfer type under strong electric fields.
Conclusions:
- * Elucidates the physical mechanism of electric-field regulated excited states in assembled endohedral metallofullerene dimers.
- * Provides theoretical guidance for designing molecular-scale optoelectronic and quantum devices.
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