# Frequency dispersion of the first hyperpolarizabilities of reference molecules for nonlinear optics

## Abstract

The frequency dispersion of the hyper-Rayleigh scattering first hyperpolarizabilities (β{sub HRS}) of five reference molecules for nonlinear optics, namely, carbon tetrachloride, chloroform, dichloromethane, acetonitrile, and trichloroacetonitrile, is described using the coupled-cluster singles and doubles quadratic response function (CCSD-QRF) as well as approximate schemes. Comparisons to approximate schemes in which the frequency dispersion is evaluated as either a multiplicative or an additive correction to the static hyperpolarizability yield the following observations: (i) errors of the order of 10% or less are usually encountered when using the multiplicative scheme for photon energies far from the lowest dipole-allowed excitation energies, (ii) spurious cases cannot be excluded as evidenced by carbon tetrachloride where the multiplicative scheme predicts a decrease of β{sub HRS} in contradiction to the increase obtained using the CCSD-QRF method, and (iii) the additive scheme is at best as reliable as the multiplicative approximation. The two-state approximation presents the advantage of correcting the wrong behavior of the additive and multiplicative schemes for carbon tetrachloride, but it is not an improved solution for the other compounds, while the question of selecting the appropriate dominant excited state remains unanswered. Finally, a new β{sub xyz} value of 18.9 a.u. is proposed for carbon tetrachloride inmore »

- Authors:

- Laboratoire de Chimie Théorique, Unité de Chimie Physique Théorique et Structurale, Université de Namur, rue de Bruxelles, 61, B-5000 Namur (Belgium)
- Institut des Sciences Moléculaires (ISM, UMR 5255 CNRS), Université de Bordeaux, 351 Cours de la Libération, F-33405 Talence Cedex (France)

- Publication Date:

- OSTI Identifier:
- 22415785

- Resource Type:
- Journal Article

- Journal Name:
- Journal of Chemical Physics

- Additional Journal Information:
- Journal Volume: 142; Journal Issue: 19; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACETONITRILE; ADDITIVES; CARBON TETRACHLORIDE; CHLOROFORM; COMPARATIVE EVALUATIONS; CORRECTIONS; EXCITATION; EXCITED STATES; METHYLENE CHLORIDE; MOLECULES; NONLINEAR OPTICS; PHOTONS; RAYLEIGH SCATTERING; RESPONSE FUNCTIONS; U VALUES; YIELDS

### Citation Formats

```
Wergifosse, Marc de, Champagne, Benoît, and Castet, Frédéric.
```*Frequency dispersion of the first hyperpolarizabilities of reference molecules for nonlinear optics*. United States: N. p., 2015.
Web. doi:10.1063/1.4920977.

```
Wergifosse, Marc de, Champagne, Benoît, & Castet, Frédéric.
```*Frequency dispersion of the first hyperpolarizabilities of reference molecules for nonlinear optics*. United States. doi:10.1063/1.4920977.

```
Wergifosse, Marc de, Champagne, Benoît, and Castet, Frédéric. Thu .
"Frequency dispersion of the first hyperpolarizabilities of reference molecules for nonlinear optics". United States. doi:10.1063/1.4920977.
```

```
@article{osti_22415785,
```

title = {Frequency dispersion of the first hyperpolarizabilities of reference molecules for nonlinear optics},

author = {Wergifosse, Marc de and Champagne, Benoît and Castet, Frédéric},

abstractNote = {The frequency dispersion of the hyper-Rayleigh scattering first hyperpolarizabilities (β{sub HRS}) of five reference molecules for nonlinear optics, namely, carbon tetrachloride, chloroform, dichloromethane, acetonitrile, and trichloroacetonitrile, is described using the coupled-cluster singles and doubles quadratic response function (CCSD-QRF) as well as approximate schemes. Comparisons to approximate schemes in which the frequency dispersion is evaluated as either a multiplicative or an additive correction to the static hyperpolarizability yield the following observations: (i) errors of the order of 10% or less are usually encountered when using the multiplicative scheme for photon energies far from the lowest dipole-allowed excitation energies, (ii) spurious cases cannot be excluded as evidenced by carbon tetrachloride where the multiplicative scheme predicts a decrease of β{sub HRS} in contradiction to the increase obtained using the CCSD-QRF method, and (iii) the additive scheme is at best as reliable as the multiplicative approximation. The two-state approximation presents the advantage of correcting the wrong behavior of the additive and multiplicative schemes for carbon tetrachloride, but it is not an improved solution for the other compounds, while the question of selecting the appropriate dominant excited state remains unanswered. Finally, a new β{sub xyz} value of 18.9 a.u. is proposed for carbon tetrachloride in gas phase at λ = 1064 nm, to be compared with the measured 16.9 ± 1.4 a.u. value due to Shelton.},

doi = {10.1063/1.4920977},

journal = {Journal of Chemical Physics},

issn = {0021-9606},

number = 19,

volume = 142,

place = {United States},

year = {2015},

month = {5}

}