Electron-phonon coupling and vibrational properties of size-selected linear carbon chains by resonance Raman scattering

• DOI: 10.1038/s41467-022-32801-3
• Publication Date: 2022-08-27T08:02:44Z
• Authors: P. Marabotti; M. Tommasini; C. Castiglioni; P. Serafini; S. Peggiani; M. Tortora; B. Rossi; A. Li Bassi; V. Russo; C. S. Casari
• Keywords: Overtone; Vibronic coupling

UV resonance Raman spectroscopy of size-selected linear sp-carbon chains unveils vibrational overtones and combinations up to the fifth order. Thanks tunability synchrotron source, we excited each H-terminated polyyne (HCnH with n = 8,10,12) maxima its vibronic absorption spectrum allowing us precisely determine electronic structure ground states for main observed mode. Selected transitions are shown enhance specific overtone orders in a way that can be explained by simple analytical model based on Albrecht's theory scattering. The determined Huang-Rhys factors indicate strong size-dependent electron-phonon coupling increasing chain length.