TY - JOUR

T1 - The depolarized Raman ν23 overtone of CO2

T2 - A line-mixing shape analysis

AU - Verzhbitskiy, I. A.

AU - Kouzov, A. P.

AU - Rachet, F.

AU - Chrysos, M.

PY - 2011/5/21

Y1 - 2011/5/21

N2 - In a recent article we showed that the 2ν3 transition of CO2 gives rise to a Raman spectrum that is almost entirely depolarized [M. Chrysos, I. A. Verzhbitskiy, F. Rachet, and A. P. Kouzov, J. Chem. Phys. 134, 044318 (2011)]. In the present article, we go further forward in the study of this overtone by reporting a first-principles shape analysis of its depolarized spectrum at room temperature. As a first step in our analysis, a model assuming isolated Lorentzian line shapes was applied, which at low gas densities turns out to be sufficient for qualitative conclusions. As the next step, a sophisticated approach was developed on the basis of the extended strong-collision model in order to properly account for the heavy line mixing between rotational lines. Whereas a marked deviation between model and measured spectra was observed upon application of the simpler model, striking agreement even at the highest CO2 density was found on applying the sophisticated one. Accurate calculated data were used for the rotational line broadening coefficients without resort to arbitrary parameters. Values for the vibrational shift scaling linearly with the density of the gas are given.

AB - In a recent article we showed that the 2ν3 transition of CO2 gives rise to a Raman spectrum that is almost entirely depolarized [M. Chrysos, I. A. Verzhbitskiy, F. Rachet, and A. P. Kouzov, J. Chem. Phys. 134, 044318 (2011)]. In the present article, we go further forward in the study of this overtone by reporting a first-principles shape analysis of its depolarized spectrum at room temperature. As a first step in our analysis, a model assuming isolated Lorentzian line shapes was applied, which at low gas densities turns out to be sufficient for qualitative conclusions. As the next step, a sophisticated approach was developed on the basis of the extended strong-collision model in order to properly account for the heavy line mixing between rotational lines. Whereas a marked deviation between model and measured spectra was observed upon application of the simpler model, striking agreement even at the highest CO2 density was found on applying the sophisticated one. Accurate calculated data were used for the rotational line broadening coefficients without resort to arbitrary parameters. Values for the vibrational shift scaling linearly with the density of the gas are given.

UR - http://www.scopus.com/inward/record.url?scp=79957623841&partnerID=8YFLogxK

U2 - 10.1063/1.3580278

DO - 10.1063/1.3580278

M3 - Article

AN - SCOPUS:79957623841

VL - 134

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 19

M1 - 194305

ER -