Revealing the Electronic and Molecular Structure of Randomly Oriented Molecules by Polarized Two-Photon Spectroscopy.
In this Letter, we explored the use of polarized two-photon absorption (2PA) spectroscopy, which brings additional information when compared to methods that do not use polarization control, to investigate the electronic and molecular structure of two chromophores (FD43 and FD48) based on phenylacetylene moieties. The results were analyzed using quantum chemical calculations of the two-photon transition strengths for circularly and linearly polarized light, provided by the response function formalism. On the basis of these data, it was possible to distinguish and identify the excited electronic states responsible for the lowest-energy 2PA-allowed band in both chromophores. By modeling the 2PA circular-linear dichroism, within the sum-over-essential states approach, we obtained the relative orientation between the dipole moments that are associated with the molecular structure of the chromophores in solution. This result allowed to correlate the V-shape structure of the FD48 chromophore and the quantum-interference-modulated 2PA strength.
†Instituto de Fı́sica de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970 São Carlos, SP, Brazil.
Marcelo G
MG
Vivas
‡Instituto de Fı́sica, Universidade de São Paulo, CP 66318, 05314-970 São Paulo, SP, Brazil.
Daniel L
DL
Silva
†Instituto de Fı́sica de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970 São Carlos, SP, Brazil.
Leonardo
L
De Boni
§CNRS, Université Lyon I, ENS-Lyon, 46 allée d'Itale, 69364 Lyon, France.
Yann
Y
Bretonniere
§CNRS, Université Lyon I, ENS-Lyon, 46 allée d'Itale, 69364 Lyon, France.
Chantal
C
Andraud
⊥Laboratoire de Chimie, CNRS UR 5182, ENS de Lyon, Université Lyon I, 46 allée d'Italie, 69364 Lyon cedex 07, France.
Florence
F
Laibe-Darbour
⊥Laboratoire de Chimie, CNRS UR 5182, ENS de Lyon, Université Lyon I, 46 allée d'Italie, 69364 Lyon cedex 07, France.
J-C
JC
Mulatier
#Theoretical Chemistry Group, Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland.
Robert
R
Zaleśny
#Theoretical Chemistry Group, Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland.
Wojciech
W
Bartkowiak
‡Instituto de Fı́sica, Universidade de São Paulo, CP 66318, 05314-970 São Paulo, SP, Brazil.
Sylvio
S
Canuto
†Instituto de Fı́sica de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970 São Carlos, SP, Brazil.
Cleber R
CR
Mendonca
density functional theory; polarized two-photon absorption spectroscopy; randomly oriented chromophores; response functions formalism; sum-over-essential states approach