Prediction Of Line-shape Parameters And Their Temperature Dependences By Requantized Classical Molecular Dynamics Simulations

Tran, Ha

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https://hdl.handle.net/2142/111222 Copy

Description

Title

Prediction Of Line-shape Parameters And Their Temperature Dependences By Requantized Classical Molecular Dynamics Simulations

Author(s)

Tran, Ha

Contributor(s)

• NGUYEN, Huyen Trang
• NGO, Ngoc Hoa

Issue Date

2021-06-22

Keyword(s)

Lineshapes, collisional effects

Abstract

We show in this talk that requantized classical molecular dynamics simulations (rCMDSs) are capable of predicting various refined spectral-shape parameters of absorption lines of linear molecules such as CO2, N2O and O2 with high precision. Combining CMDSs and a requantization procedure, we computed the auto-correlation function of the dipole moment responsible for the absorption transition. Its Fourier-Laplace transform directly yields the spectrum. Calculations were made for various temperature conditions, at 1 atm and for a large range of Doppler widths, from the near-Doppler to the collision-dominant regimes. For each temperature and each line, the spectra calculated for various Doppler widths were simultaneously fit with a refined line-shape model. The latter takes into account the effects of the speed dependent collisional line broadening, the Dicke narrowing, and the collisional line mixing. The obtained parameters were then directly compared with those deduced from high-precision measurements. The results show very good agreements, even for those parameters whose influence on the spectra is very small. Good agreement is also obtained between measured and predicted temperature dependences of these parameters. This demonstrates that rCMDS is an excellent tool, highly competitive with respect to high quality measurements for precise line-shape studies.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Permalink

http://hdl.handle.net/2142/111222

DOI

10.15278/isms.2021.TM14

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