Vibronic coupling in the ground and excited states of the naphthalene cation

Abstract

The hole-vibrational coupling in naphthalene is studied using high-resolution gas-phase photoelectron spectroscopy and density functional theory calculations (DFT), and a remarkable increase of the coupling with low-frequency vibrations is observed in the excited states.

First Principles Quantum Dynamical Investigation Provides Evidence for the Role of Polycyclic Aromatic Hydrocarbon Radical Cations in Interstellar Physics

“…The results reveal resolved bands for theX,Ã, andB and highly overlapping bands for theC-D-Ẽ electronic states. The results are in good accord with the available photoelectron spectroscopy data [9,10]. A detailed presentation of the theoretical data is out of the scope of this Letter; we therefore focus on the important results that provide an understanding of recent novel astrophysical discovery.…”

“…The consensus is that they originate from electronically excited radical cations of polycyclic aromatic hydrocarbons (PAHs), most abundant in the interstellar medium (ISM) [2]. This PAH hypothesis inspired new laboratory measurements in the typical conditions of ISM which revealed diffuse vibronic bands and subpicosecond dynamics of their low-lying electronic states [3][4][5][6][7][8][9][10]. Very recently, spectroscopic measurements of the star Cernis 52 located in the Perseus molecular cloud led to the discovery of three new DIBs [11].…”

Assessment of density-functional models for organic molecular semiconductors: The role of Hartree–Fock exchange in charge-transfer processes

“…Interestingly, the RMS errors are notoriously reduced with respect to B3LYP by up to 35% despite the fact that fitting of the gas-phase photoelectron spectra of these molecules was done with the information (harmonic vibrational fre- BLYP 146 148 101 101 78 80 63 65 52 50 27 27 B1LYP 200 201 152 154 126 129 109 114 15 15 8 8 BHHLYP 266 269 220 222 194 197 179 182 66 68 34 35 HF-LYP 440 440 403 403 426 406 396 400 267 263 134 132 PBE 141 144 97 98 74 77 59 60 56 54 28 28 PBE0 194 197 148 150 121 125 104 108 14 14 8 8 PBEHH 261 265 214 217 188 192 172 170 60 62 31 32 HF-PBE 433 439 395 401 382 388 386 394 250 256 126 a Taken from Ref. [117] (naphtalene) and Ref. [118] (anthracene, tetracene, and pentacene).…”

Hole-vibronic coupling in oligothiophenes: impact of backbone torsional flexibility on relaxation energies

“…The B3LYP functional has a good track record for describing the vibronic properties of the charged states of oligoacenes (Coropceanu et al 2002b;Gruhn et al 2002;da Silva et al 2004;Malagoli et al 2004;Sánchez-Carrera et al 2006) and anthradithiophene (Kwon et al 2004). However, recent investigations (Geskin & Bredas 2003) of the geometric and electronic structure and charge localization in radical cations of oligothiophene chains favour the BHandHLYP functional (which includes a higher percentage of Hartree-Fock exchange) as the better choice for these systems.…”