14 research outputs found
Le spectre de H2S entre 2150 et 2950 cm-1 : positions et intensites des raies
SIGLET 55665 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Spectre infrarouge de H2S dans les regions spectrales de 4x10-6m et 1.6x10-6m : positions et intensites des raies
SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
THE SPECTRUM BETWEEN 2150 AND : LINE POSITIONS AND INTENSITIES
Author Institution: Laboratoire de Physique Mol\'{e}culaire et d'Optique Atmosph\'{e}rique, C.N.R.S, B\v{a}timent 221; Herzberg Institute of Astrophysics, N.R.C, OttawaSpectra of natural hydrogen sulfide have been recorded between 2150 and on a Bomem spectrophotometer with a resolution of . The careful analysis of the and bands of the three species and has led to a complete and precise set of rotational energy levels of the three vibrational interacting states (020), (100) and (001) for the three isotopes. Then using these data we have been able to determine the rotational and coupling constants involved in the upper-states Hamiltonian. About 530 line intensities of were measured from which precise transition moments of the 3 bands under study were derived leading to the determination of the first derivatives of the dipole moment with respect to the normal coordinates and . Besides it is to be pointed out that the strong intensity anomalies appearing in the band are well reproduced by the calculation. Finally the complete spectrum of natural hydrogen sulfide has been computed
The far infrared spectrum of H2O2 observed and calculated rotational levels of the torsional states : (n, Ï) = (0, 1), (0, 3) and (1, 1)
High resolution Fourier transform spectra, recorded between 30 and 460 cm-1, have been used for an extensive analysis of the (n, Ï) = (0, 3) â (n', Ï') = (0, 1), (0,1) â (0, 3) and (1, 1) â (0, 3) torsion-rotation bands of H2O2. Then, using a Hamiltonian which takes explicitly into account the strong |ÎKa| = 2 interaction between the rotational levels of the (n, Ï) = (0,1) and (1,1) torsional states, as well as the |ÎKa| = 2 interaction between the (n, Ï) = (1, 1) and (2, 1) rotational levels, it has been possible to reproduce very satisfactorily the experimental rotational levels of the (n, Ï) = (0, 1) and (1,1) torsional states and a precise set of torsional energies and rotational and coupling constants has been derived. In the same way, to fit the (n, Ï) = (0, 3) experimental energy levels we have used a Hamiltonian taking into account the |ÎKa| = 2 interaction between the rotational levels of the (n, Ï) = (0, 3) and (1, 3) torsional states, and this calculation has also provided a precise set of torsional energies, rotational and coupling constants for the (n, Ï) = (0, 3) and (1, 3) torsional states.Des spectres par transformĂ©e de Fourier Ă haute rĂ©solution enregistrĂ©s entre 30 et 460 cm-1 ont Ă©tĂ© utilisĂ©s pour une analyse systĂ©matique des bandes de torsion-rotation (n, Ï) = (0, 3) â (n', Ï') = (0,1), (0,1) â (0, 3) et (1, 1) â (0, 3) de H2O 2. L'utilisation d'un hamiltonien qui traite explicitement la forte interaction de type |ÎKa| = 2 entre les niveaux rotationnels des Ă©tats de torsion (n, Ï) = (0, 1) et (1,1) ainsi que l'interaction en |ÎKa| = 2 entre les niveaux de (n, Ï) = (1,1) et (2, 1), a permis de reproduire de façon trĂšs satisfaisante les niveaux observĂ©s des Ă©tats de torsion (n, Ï) = (0,1) et (1,1) tout en foumissant un ensemble prĂ©cis d'Ă©nergies de torsion et de constantes rotationnelles et de couplage. De la mĂȘme façon pour reproduire les niveaux observĂ©s de (n, Ï)= (0, 3) a Ă©tĂ© utilisĂ© un hamiltonien qui tient compte de l'interaction en |ÎK a| = 2 entre les niveaux rotationnels des Ă©tats de torsion (n, Ï) = (0, 3) et (1, 3) et des Ă©nergies de torsion et des constantes rotationnelles et de couplage prĂ©cises ont Ă©tĂ© ainsi dĂ©terminĂ©es pour ces Ă©tats