The spectroscopy of a prototypical indolenine-based squaraine dye is analysed theoretically using state-of-the-art methodologies for the simulation of spectral lineshapes, and experimentally using optical absorption and emission spectroscopies. Density functional theory and its time-dependent extension are used to determine the stability of several conformers, to compute their excitation energies, equilibrium geometries and vibrational frequencies, both in the ground and in their first excited singlet state. Finally the generating function approach is used to simulate the vibronic lineshape of the low energy valence ππ* excitation and emission spectra. Solvent effects are also computed and discussed by using the polarizable continuum model. The developed model correctly reproduces the main spectral features of the squaraine, and allows us to identify the vibrational motions that mainly contribute to the observed lineshape.

Theoretical and experimental determination of the absorption and emission spectra of a prototypical indolenine-based squaraine dye

BORRELLI, Raffaele;ELLENA, Silvano;BAROLO, CLAUDIA
2014-01-01

Abstract

The spectroscopy of a prototypical indolenine-based squaraine dye is analysed theoretically using state-of-the-art methodologies for the simulation of spectral lineshapes, and experimentally using optical absorption and emission spectroscopies. Density functional theory and its time-dependent extension are used to determine the stability of several conformers, to compute their excitation energies, equilibrium geometries and vibrational frequencies, both in the ground and in their first excited singlet state. Finally the generating function approach is used to simulate the vibronic lineshape of the low energy valence ππ* excitation and emission spectra. Solvent effects are also computed and discussed by using the polarizable continuum model. The developed model correctly reproduces the main spectral features of the squaraine, and allows us to identify the vibrational motions that mainly contribute to the observed lineshape.
2014
16
6
2390
2398
Coloring Agents; indoles; Fluorescence; Dyes
Raffaele Borrelli; Silvano Ellena; Claudia Barolo
File in questo prodotto:
File Dimensione Formato  
isq_unito.pdf

Accesso aperto

Tipo di file: PREPRINT (PRIMA BOZZA)
Dimensione 3.64 MB
Formato Adobe PDF
3.64 MB Adobe PDF Visualizza/Apri
c3cp54298j.pdf

Accesso riservato

Tipo di file: PDF EDITORIALE
Dimensione 1.67 MB
Formato Adobe PDF
1.67 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/157809
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 29
  • ???jsp.display-item.citation.isi??? 29
social impact