0000000000033587

AUTHOR

Olga Vasilievna Gromova

High resolution study of the 3ν1 band of SO2

Abstract The second overtone band 3 ν 1 of sulfur dioxide has been studied for the first time with high resolution rotation-vibration spectroscopy. About 3000 transitions involving about 900 upper state energy levels with J max. = 66 and K a max. = 24 have been assigned to the 3 ν 1 band. In the analysis, an effective Hamiltonian taking into account accidental interactions between the vibrational states (3 0 0), (2 2 0), and (0 4 1) was used. The Watson operator in A -reduction and I r representation was used in the diagonal blocks of the Hamiltonian. As the result of analysis a set of parameters reproducing the initial experimental data with the rms = 0.00028 cm −1 was obtained.

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Analysis of highly excited 'hot' bands in the SO2 molecule: ν2 + 3ν3 - ν2 and 2ν1 + ν2 + ν3 - ν2

International audience; We set up a variational procedure of assignments of transitions and we applied it to the analysis very weak 'hot' bands, v(2) + 3v(3) - v(2) and 2v(1) + v(2) + v(3) - v(2), of the SO2 molecule. As the first step of the study, the 'cold' bands, 3v(3) and 2v(1) + v(3), are re-analysed and transitions belonging to those bands are assigned up to the values of quantum numbers J(max.) = 60, K-a(max.) = 19, and J(max.) = 69, K-a(max.) = 20 for the bands 3v(3) and 2v(1) + v(3), respectively. After 'cleaning' the experimental spectrum from transitions belonging to the 3v(3) and 2v(1) + v(3) bands, a variational procedure was used that allowed us to assign 230 and 115 transiti…

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On the determination of the intramolecular potential energy surface of polyatomic molecules: Hydrogen sulfide and formaldehyde as an illustration

International audience; We present here an approach for determining the Hamiltonian of polyatomic molecules that allows one to successfully solve the problem of potential energy surface (PES) determination via construction and diagonalization of a Hamiltonian matrix of large dimension. In the suggested approach, the Hamiltonian is very simple and can be used both for any "normal" polyatomic molecule and for any isotopic species of a molecule. Molecules with two to four equivalent X-Y bonds are considered, and for illustration of the efficiency of the suggested approach, numerical calculations are made for the three-atomic (hydrogen sulfide) and four-atomic (formaldehyde) molecules.

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High resolution study of the and “hot” bands and ro-vibrational re-analysis of the polyad of the 32SO2 molecule

Abstract The weak “hot” absorption bands, ν 1 + 2 ν 2 − ν 2 and 2 ν 2 + ν 3 − ν 2 , were analysed with high resolution using the Fourier transform interferometer Bruker IFS-120 HR. In order to make possible an analysis of the ν 1 + 2 ν 2 − ν 2 and 2 ν 2 + ν 3 − ν 2 bands, as the first step, we re-analysed considerably the stronger “cold” bands, ν 1 + ν 2 and ν 2 + ν 3 , which are located in the same spectral regions. As the result of analysis we obtained about 2650 and 2050 transitions (1069 and 1001 upper state ro-vibrational energy values) with Jmax. = 78, Kamax. = 27 and Jmax. = 68, Kamax. = 24 for the bands ν 1 + ν 2 and ν 2 + ν 3 , respectively, that is considerably higher than in the …

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Study of resonance interactions in polyatomic molecules on the basis of highly accurate experimental data: Set of strongly interacting Bands ν10(B1), ν7(B2), ν4(A2), ν8(B2), ν3(A1) and ν6(B1) of CH2=CD2

Abstract The highly accurate (experimental accuracy in line positions ~ ( 1 − 3 ) × 10 − 4 cm − 1 ) FTIR ro-vibrational spectra of CH2=CD2 in the region of 600–1300 cm−1, where the fundamental bands ν10, ν7, ν4, ν8, ν3, and ν6 are located, were recorded and analyzed with the Hamiltonian model which takes into account resonance interactions between all six studied bands. About 12 200 ro-vibrational transitions belonging to these bands (that is considerably more than it was made in the preceding studies for the bands ν10, ν7, ν8, ν3 and ν6; transitions belonging to the ν4 band were assigned for the first time) were assigned in the experimental spectra with the maximum values of quantum number…

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High-resolution IR spectrum of AsH2D: Ro-vibrational analysis of the bending triad bands , , and

Abstract The infrared spectrum of the AsH2D molecule has been measured in the region of the three bending fundamental bands on a Fourier transform spectrometer with a resolution of 0.0024 cm−1 and analyzed for the first time. More than 7500 normally allowed and in addition about 600 forbidden, but perturbation-activated transitions with J max = 21 , K a max = 20 and K c max = 21 have been assigned to the bands ν 3 , ν 4 , and ν 6 . The measured transition wavenumbers were used to determine 1047 upper energy values. These energies were fitted with a Watson-type Hamiltonian in A reduction and IIIl representation taking into account resonance interactions between all three bending states, (001…

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High resolution analysis of the SO2 spectrum in the 2600–2900cm−1 region: 2ν3, ν2+2ν3−ν2 and 2ν1+ν2 bands

Abstract Infrared spectrum of the SO 2 molecule was recorded with high resolution in the 2600– 2900 cm − 1 region. Spectrum was recorded with the Fourier transform interferometer Bruker IFS-120 HR in Oulu (Finland) with the pressure of 111 Pa and the absorption path length of 163.2 m that allowed us to record 2 ν 3 and 2 ν 1 + ν 2 weak bands. The 2 ν 3 band discussed earlier by Lafferty et al., was re-analyzed, and considerably more information was extracted from the spectrum (more than 3800 transitions of the 2 ν 3 band were assigned in the experimental spectrum with maximum values of quantum numbers, J max . = 76 and K a max . = 26 ). On the basis of the procedure discussed in Ulenikov et…

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On the ‘expanded local mode’ approach applied to the methane molecule: isotopic substitution CH2D2←CH4

On the basis of a compilation of the ‘expanded local mode’ model and the general isotopic substitution theory, sets of simple analytical relations between different spectroscopic parameters (harmonic frequencies, ωλ, anharmonic coefficients, x λμ, ro-vibrational coefficients, , different kinds of Fermi- and Coriolis-type interaction parameters) of the CH2D2 molecule are derived. All of them are expressed as simple functions of a few initial spectroscopic parameters of the mother, CH4, molecule. Test calculations with the derived isotopic relations show that, in spite of a total absence of initial information about the CH2D2 species, the numerical results of the calculations have a very good…

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On the high resolution spectroscopy and intramolecular potential function of SO2

Abstract Two weak stretching bands, ν 1  + 3 ν 3 and 3 ν 1  +  ν 3 , of the sulfur dioxide molecule have been recorded at high resolution and analyzed for the first time with using a Fourier transform Bruker IFS-120 HR interferometer. About 1000 transitions with J max .  = 51, K a max . = 16 , and 900 transitions with J max .  = 53, K a max . = 16 have been assigned to the bands ν 1  + 3 ν 3 and 3 ν 1  +  ν 3 , respectively. Analysis of the recorded spectra was made using the model of isolated vibrational states. Parameters obtained from the fit reproduce the initial experimental ro-vibrational energies with the rms deviation of 0.0006 and 0.0012 cm −1 for the bands, 3 ν 1  +  ν 3 and ν 1  …

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