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Reference molecules for nonlinear optics: a joint experimental and theoretical investigation.
Frédéric Castet1, Elena Bogdan, Aurélie Plaquet
1Université de Bordeaux, Institut des Sciences Moléculaires, 351 Cours de la Libération, 33405 Talence, France. f.castet@ism.u-bordeaux1.fr
The Journal of Chemical Physics
|January 21, 2012
Summary
Hyper-Rayleigh scattering (HRS) experiments reveal molecular symmetry's impact on nonlinear optical responses. This technique accurately probes molecular symmetry, aiding in understanding optical properties.
Area of Science:
- Nonlinear Optics
- Quantum Chemistry
- Molecular Spectroscopy
Background:
- The second-order nonlinear optical (NLO) response is crucial for understanding molecular interactions with light.
- Molecular symmetry plays a significant role in determining NLO properties.
- Hyper-Rayleigh scattering (HRS) is a powerful experimental technique for probing NLO phenomena.
Purpose of the Study:
- To investigate the second-order NLO responses of various reference molecules.
- To elucidate the influence of molecular symmetry on NLO properties using multipolar decomposition.
- To establish HRS as a reliable method for assessing molecular symmetry.
Main Methods:
- Combined experimental Hyper-Rayleigh scattering (HRS) with quantum chemical calculations.
- Employed multipolar decomposition of the first hyperpolarizability tensor using spherical harmonics formalism.
- Utilized coupled-cluster calculations (singles, doubles, and perturbative triples) with extensive basis sets and the polarizable continuum model for environment effects.
Main Results:
- Demonstrated that HRS is highly effective in probing molecular symmetry.
- Qualitatively reproduced experimental molecular first hyperpolarizabilities and depolarization ratios.
- Highlighted the correlation between molecular symmetry and observed NLO responses.
Conclusions:
- HRS experiments combined with theoretical calculations provide deep insights into molecular NLO properties.
- Molecular symmetry is a key factor governing the second-order NLO response.
- The study validates HRS as a precise tool for symmetry analysis in molecules.
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