Laser induced dispersed fluorescence spectra of jet cooled NO2: The complete set of vibrational levels up to 10 000 cm−1 and the onset of the X̃ 2A1–Ã 2B2 vibronic interaction

Delon, Antoine; Jost, R.

doi:10.1063/1.461617

Cited by 170 publications

(135 citation statements)

References 31 publications

Supporting

Mentioning

118

Contrasting

Unclassified

Order By: Relevance

“…Consequently, overtime it became a benchmark system for a variety of spectroscopic and dynamics studies concerning theoretical and experimental aspects of photodissociation, intramolecular vibrational redistribution, nonadiabatic couplings [1,2,3,4,5,6,7,8,9,10,11,12,13]. The numerous nonadiabatic interactions are reflected in a complex photodissociation dynamics.…”

Section: Introductionmentioning

confidence: 99%

Imaging fast relaxation dynamics of NO₂

et al. 2009

View full text Add to dashboard Cite

Time-resolved spectroscopy combined with velocity map imaging technique have been used to investigate the multiphoton dynamics of NO 2 molecule. Two different pump-probe excitation schemes were used to explore different potential energy surfaces (PESs) located in the first dissociation region and in the Rydberg region around 9.2 eV. Integrated and energy resolved signals of NO + 2 , NO + and photoelectrons were recorded as a function of time. When exciting with 403 nm photons, the NO + signal exhibits an intriguing oscillatory behaviour with a period of 512 fs. The NO + and photoelectron kinetic energy distributions produced by this pump wavelength were cold, while those produced when employing 269 nm photons as pump were very rich, evidencing the presence of multiple excitation channels. A couple of sharp long lived photoion-photoelectron peaks represents the most salient feature of latter. They were assigned to an excitation by two 269 nm photons to a Rydberg state dissociating into NO(A 2 Σ + )+O( 3 P ). This NO + peak as well as another one located at 0 eV display very complex time dependencies including the signatures of two dissociation dynamics on timescales of 400 and 600 fs. The different pathways responsible of this temporal behaviour are discussed in view of shedding light onto the underlying multichannel multiphoton dynamics.

show abstract

Section: Introductionmentioning

confidence: 99%

Imaging fast relaxation dynamics of NO₂

et al. 2009

View full text Add to dashboard Cite

show abstract

“…3,4 The photoexcitation of NO 2 via the first excited state is known to be very complex due to a conical intersection coupling the ground and first excited states. The effect of this conical intersection has been extensively studied in the frequency 5,6 and more recently also the time domain. [7][8][9][10] Depending on the typical time scale of the dissociation dynamics, femtosecond pump-probe laser spectroscopy can be used.…”

Section: Introductionmentioning

confidence: 99%

Femtosecond time-resolved photoelectron-photoion coincidence imaging of multiphoton multichannel photodynamics in NO2

Vredenborg¹,

Roeterdink²,

Janssen³

2008

The Journal of Chemical Physics

View full text Add to dashboard Cite

The multiphoton multichannel photodynamics of NO 2 has been studied using femtosecond time-resolved coincidence imaging. A novel photoelectron-photoion coincidence imaging machine was developed at the laboratory in Amsterdam employing velocity map imaging and "slow" charged particle extraction using additional electron and ion optics. The NO 2 photodynamics was studied using a two color pump-probe scheme with femtosecond pulses at 400 and 266 nm. The multiphoton excitation produces both NO 2 + parent ions and NO + fragment ions. Here we mainly present the time dependent photoelectron images in coincidence with NO 2 + or NO + and the ͑NO + , e͒ photoelectron versus fragment ion kinetic energy correlations. The coincidence photoelectron spectra and the correlated energy distributions make it possible to assign the different dissociation pathways involved. Nonadiabatic dynamics between the ground state and the A 2 B 2 state after absorption of a 400 nm photon is reflected in the transient photoelectron spectrum of the NO 2 + parent ion. Furthermore, Rydberg states are believed to be used as "stepping" states responsible for the rather narrow and well-separated photoelectron spectra in the NO 2 + parent ion. Slow statistical and fast direct fragmentation of NO 2 + after prompt photoelectron ejection is observed leading to formation of NO + + O. Fragmentation from both the ground state and the electronically excited a 3 B 2 and b 3 A 2 states of NO 2 + is observed. At short pump probe delay times, the dominant multiphoton pathway for NO + formation is a 3 ϫ 400 nm+ 1 ϫ 266 nm excitation. At long delay times ͑Ͼ500 fs͒ two multiphoton pathways are observed. The dominant pathway is a 1 ϫ 400 nm+ 2 ϫ 266 nm photon excitation giving rise to very slow electrons and ions. A second pathway is a 3 ϫ 400 nm photon absorption to NO 2 Rydberg states followed by dissociation toward neutral electronically and vibrationally excited NO͑A 2 ⌺ , v =1͒ fragments, ionized by one 266 nm photon absorption. As is shown in the present study, even though the pump-probe transients are rather featureless the photoelectron-photoion coincidence images show a complex time varying dynamics in NO 2 . We present the potential of our novel coincidence imaging machine to unravel in unprecedented detail the various competing pathways in femtosecond time-resolved multichannel multiphoton dynamics of molecules.

show abstract

“…[35,36] This has also been shown in theoretical studies of HCOH isomerizations. [37] On the other hand, results when using the two lowest 1 2 A and 1 2 A PESs indicate that the 1 2 A PES might play an important role along with quantum [28] effects at temperatures below 400 K. However, for temperatures above 1000 K the results using only the 1 2 A PES reasonably match with the experimental results, e.g. for 1500 and 2700 K. This can be explained by noting that the well of the electronically excited C-state of NO 2 (C 1 2 A ) is comparatively small and leads to redissociation of NO 2 at high temperatures [11].…”

Section: Thermal Rate Coefficientsmentioning

confidence: 96%

“…Two symmetric minima are observed for the same R 3 Jacobi distance which is measured from the center of mass of O 2 to the N atom. Some features of our ground state PES are summarized in Table 1 and compared to results from previous calculations [13] (using icMRCI+Q/cc-pVQZ with CASSCF(13,10)) and to experiments [28,29,30,31,32] (high-resolution microwave spectroscopy [29] and laser induced fluorescence [31]). Good agreement with previous computations and experiments was found from the methods used in the present work.…”

Section: The Ground State 1 2 a Pesmentioning

confidence: 99%

Investigations of Reactive Processes at Temperatures Relevant to the Hypersonic Flight Regime

Meuwly¹

2014

View full text Add to dashboard Cite

Laser induced dispersed fluorescence spectra of jet cooled NO2: The complete set of vibrational levels up to 10 000 cm−1 and the onset of the X̃ 2A1–Ã 2B2 vibronic interaction

Cited by 170 publications

References 31 publications

Imaging fast relaxation dynamics of NO₂

Imaging fast relaxation dynamics of NO₂

Femtosecond time-resolved photoelectron-photoion coincidence imaging of multiphoton multichannel photodynamics in NO2

Investigations of Reactive Processes at Temperatures Relevant to the Hypersonic Flight Regime

Contact Info

Product

Resources

About

Laser induced dispersed fluorescence spectra of jet cooled NO2: The complete set of vibrational levels up to 10 000 cm−1 and the onset of the X̃ 2A1–Ã 2B2 vibronic interaction

Cited by 170 publications

References 31 publications

Imaging fast relaxation dynamics of NO2

Imaging fast relaxation dynamics of NO2

Femtosecond time-resolved photoelectron-photoion coincidence imaging of multiphoton multichannel photodynamics in NO2

Investigations of Reactive Processes at Temperatures Relevant to the Hypersonic Flight Regime

Contact Info

Product

Resources

About

Imaging fast relaxation dynamics of NO₂

Imaging fast relaxation dynamics of NO₂