Confinement Effects on UV-Visible Absorption Spectra: β-Carotene Inside Carbon Nanotube as a Test Case.
The effect of the confinement in a single-wall carbon nanotube on the optical properties of β-carotene is studied at the time-dependent density functional theory level. A complex computational protocol has been developed, based on a multilayered ONIOM approach making use of a recent range-separated hybrid functional as well as dispersion corrections. The role of both mechanical and electronic embedding has been clearly pointed out, showing how the inclusion of the latter is mandatory for a correct description of the experimental data. The correct calculation of the bathochromic shift experimentally observed upon encapsulation (0.23 eV) shows the ability of this computational protocol to reproduce all the physics behind such a complex host-guest interaction. From a more chemical point of view, this study allows one to show how such a shift is related to both geometrical and polarization effects.
†Universidad de Jaén, Paraje las Lagunillas, s/n. 23071, Jaén, Spain.|‡Laboratoire d'Electrochimie, Chimie des Interfaces et Modélisation pour l'Energie, CNRS UMR-7575, Ecole Nationale Supérieure de Chimie de Paris, Chimie ParisTech, 11 rue P. et. M. Curie, 75231 Paris Cedex 05 France.
Gregorio
G
García
‡Laboratoire d'Electrochimie, Chimie des Interfaces et Modélisation pour l'Energie, CNRS UMR-7575, Ecole Nationale Supérieure de Chimie de Paris, Chimie ParisTech, 11 rue P. et. M. Curie, 75231 Paris Cedex 05 France.
Ilaria
I
Ciofini
†Universidad de Jaén, Paraje las Lagunillas, s/n. 23071, Jaén, Spain.
Manuel
M
Fernández-Gómez
‡Laboratoire d'Electrochimie, Chimie des Interfaces et Modélisation pour l'Energie, CNRS UMR-7575, Ecole Nationale Supérieure de Chimie de Paris, Chimie ParisTech, 11 rue P. et. M. Curie, 75231 Paris Cedex 05 France.|§Institut Universitaire de France, 103 Boulevard Saint Michel, F-75005 Paris, France.
Carlo
C
Adamo
UV−vis spectra; carbon nanotube; electronic embedding; time-dependent density functional theory; β-carotene