Resonance CARS overtones of NaH in a Na (3p) + H2 gas mixture

Correia, Ricardo Rego Bordalo; Cunha, Silvio Luiz Souza; Vivie‐Riedle, Regina de; Pichler, Goran; Kompa, K. L.; Hering, P.

doi:10.1016/0009-2614(91)90463-j

Cited by 15 publications

(4 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sodium atoms in the gas phase (n"6·10 cm\) are excited in the 3p level by a flashlamp-pumped dye laser. Via collisions between excited sodium atoms and hydrogen molecules sodium hydride is produced [14,16]. The concentration of NaH-molecules in vibrational levels up to v"3 is sufficient for our spectroscopic study.…”

Section: Methodsmentioning

confidence: 94%

“…Since 1990 our group [14] has investigated the formation of NaH via collisions of excited sodium atoms with molecular hydrogen in the gas phase by resonance coherent anti-Stokes-Raman-Scattering (RECARS) and DFWM. Although the spectroscopic features of NaH seemed to be well known unexpected difficulties appeared in assigning new spectral lines, which we identified later as NaH-lines.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

New Dunham coefficients of the A 1 ∑ +-State of NaH and NaD

Lochbrunner

Motzkus

Pichler

et al. 1996

Z Phys D - Atoms, Molecules and Clusters

Self Cite

View full text Add to dashboard Cite

We determined new Dunham coefficients of the A >-State of NaH and NaD from degenerate FourWave-Mixing (DFWM) spectra in the near UV and in the blue spectral region. In the case of NaH we combined these data with results of Rafi et al. and Orth et al.. The new set of coefficients describes the vibrational dependence of the rotational constants B and D and of the band origins from v"0 up to 25. The spectral positions of the lines in our DFWM-spectra can be reproduced by this coefficients with an accuracy better than 0.3 cm\ for J-values415 and 2 cm\ for J-values 425. Especially for high J-values this is an improvement up to 30 times in comparison to Dunham coefficients recommended before. A RKR-potential of the A >-state was calculated with the new coefficients. The Dunham coefficients of NaD were obtained by scaling the NaH coefficients with the reduced masses of the molecules. A comparison of our results to molecular constants determined from the measured NaD-spectra shows good agreement.

show abstract

Section: Methodsmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

New Dunham coefficients of the A 1 ∑ +-State of NaH and NaD

Lochbrunner

Motzkus

Pichler

et al. 1996

Z Phys D - Atoms, Molecules and Clusters

Self Cite

View full text Add to dashboard Cite

show abstract

“…Many of these systems are not accessible to fluorescence detection due to the nature of the reactive potentials, or a low collision cross section, or due to a luminous environment. For the system of interest here, the Na+H 2 , which serves as a typical example of collisions between excited alkali atoms and simple molecules, extensive experimental research has been carried out in the nanosecond regime. − Recently, quantum mechanical calculations have also been performed to describe the dynamics of the collision process. − The experimental condition involves the full collision of Na and H 2 (or He), in a heat pipe, and with this arrangement we discuss the approach and some initial results. Three different experimental realizations which aim at revealing the dynamics on different surfaces are discussed.…”

Section: Introductionmentioning

confidence: 99%

“…For the system of interest here, the Na+H 2 , which serves as a typical example of collisions between excited alkali atoms and simple molecules, extensive experimental research has been carried out in the nanosecond regime. [36][37][38][39][40][41][42][43][44] Recently, quantum mechanical calculations have also been performed to describe the dynamics of the collision process. [45][46][47] The experimental condition involves the full collision of Na and H 2 (or He), in a heat pipe, and with this arrangement we discuss the approach and some initial results.…”

Section: Introductionmentioning

confidence: 99%

Femtosecond Real-Time Probing of Reactions. 19. Nonlinear (DFWM) Techniques for Probing Transition States of Uni- and Bimolecular Reactions

1996

View full text Add to dashboard Cite

Degenerate four-wave mixing (DFWM), using ∼60 femtosecond (fs) laser pulses, is introduced to study transition-state dynamics of chemical reactions in the gas phase. The ultrafast techniques are applied to a range of systems, atomic, unimolecular, and bimolecular. It is shown how fs DFWM can be incorporated in different temporal pulse schemes to extract the dynamics. The DFWM beams are configured in a folded boxcar geometry, producing a spatially separated, background-free, femtosecond signal pulse. Aspects of the technique, such as absorption, are investigated. We have taken advantage of the relatively broad spectral width of the fs pulses and extended the techniques to two-color grating experiments in the gas phase. The unimolecular system, NaI, provided a means of testing this new approach. Our experimental observations of the wave packet motion are in excellent agreement with results obtained using laser-induced fluorescence (LIF). A control experiment was also performed on this system, demonstrating the advantages of the nonlinear technique. Bimolecular reactions were initiated for the system Na+H 2 . Atomic sodium was investigated with fs DFWM and the oscillatory wave packet behavior (2 ps period) was observed, corresponding to the fine structure splitting of the 3p level (17.2 cm -1 ). We also explored the application of fs DFWM to the reactive and nonreactive collisions of the Na+H 2 system, which serves as a good model for studying dynamics of nonadiabatic quenching processes and collision complexes.

show abstract

Partial widths of feshbach funnel resonances in the Na(3p) � H2 exciplex

Mielke

Tawa

Truhlar

et al. 1993

Int. J. Quantum Chem.

View full text Add to dashboard Cite

We have located five zero-angular-momentum resonance states in the funnel associated with the lowest conical intersection of the Na( 3p) * H1 exciplex, and we have characterized the four narrowest of these in terms of total and partial widths. The resonant contributions of the metastable states to state-testate energy transfer greatly exceed the background contributions. 0 1993 John Wiley & Sons, Inc.

show abstract

Resonance CARS overtones of NaH in a Na (3p) + H2 gas mixture

Cited by 15 publications

References 11 publications

New Dunham coefficients of the A 1 ∑ +-State of NaH and NaD

New Dunham coefficients of the A 1 ∑ +-State of NaH and NaD

Femtosecond Real-Time Probing of Reactions. 19. Nonlinear (DFWM) Techniques for Probing Transition States of Uni- and Bimolecular Reactions

Partial widths of feshbach funnel resonances in the Na(3p) � H2 exciplex

Contact Info

Product

Resources

About