Polarization of Valence Orbitals by the Intramolecular Electric Field from a Diffuse Dipole-Bound Electron

• Published in: The journal of physical chemistry letters Vol. 11; no. 18; pp. 7914 - 7919
• Main Authors: Yuan, Dao-Fu, Liu, Yuan, Qian, Chen-Hui, Kocheril, G. Stephen, Zhang, Yue-Rou, Rubenstein, Brenda M, Wang, Lai-Sheng
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 17.09.2020
• Subjects: Anions; Electric fields; Electrical energy; Excited states; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Molecules; Physical Insights into Light Interacting with Matter
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/acs.jpclett.0c02514

The diffuse electron in a dipole-bound state is spatially well separated from the valence electrons and is known to have negligible effects on the dipole-bound state’s molecular structure. Here, we show that a dipole-bound state is observed in deprotonated 4-(2-phenylethynyl)-phenoxide anions, 348 cm–1 below the anion’s detachment threshold. The photodetachment of the dipole-bound electron is observed to accompany a simultaneous shakeup process in valence orbitals in this aromatic molecular anion. This shakeup process is due to configuration mixing as a result of valence orbital polarization by the intramolecular electric field of the dipole-bound electron. This observation suggests that dipole-bound anions can serve as a new platform to probe how oriented electric fields influence the valence electronic structure of polyatomic molecules.