Circular Dichroism in Photoionization of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi mathvariant="normal">H</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>

Dowek, D.; Pérez-Torres, Jhon Fredy; Picard, Y. J.; Billaud, P.; Elkharrat, C.; Houver, J. C.; Sanz-Vicario, José Luis; Martín, Fernando

doi:10.1103/physrevlett.104.233003

Cited by 44 publications

(42 citation statements)

References 31 publications

(49 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The present results show, in agreement with what was anticipated in Ref. [28] for H 2 , that for both molecular isotopes CD is possible due to the interference between direct photoionization and delayed autoionization from the Q 1 and Q 2 doubly excited states into ionic H 2 + states of different inversion symmetry (1sσ g and 2pσ u ). These interferences change dramatically as a function of the nuclear kinetic energy [29].…”

Section: Introductionsupporting

confidence: 81%

“…When photoionization is fast in comparison with dissociation of the molecular ion [20], variations with total energy are entirely due to variations in the photoelectron energy, since the nuclei barely move and therefore their kinetic energy remains nearly constant [20]. However, when, as in the present study, both ionization and dissociation occur on a comparable time scale, the energy in the final state is shared between electrons and nuclei, and consequently the F LN (θ e ) functions do vary with the photoion kinetic energy [28,32]. We will use this dependence upon θ e and the photoion kinetic energy to present and discuss our results.…”

Section: Circular Dichroism For Photoemission In the Molecular Framementioning

confidence: 60%

“…This is an extension of our previous work reported in [28], where a more limited photon energy range was considered and resonant effects were investigated only for H 2 . The present results show, in agreement with what was anticipated in Ref.…”

Section: Introductionmentioning

confidence: 71%

“…From our previous studies in H 2 [28] we have learned that CD effects occur at proton kinetic energies where DPI through both the 1sσ g and 2pσ u channels is possible. At these proton kinetic energies, CD is almost entirely determined by autoionization from the Q 1 and Q 2 doubly excited states of H 2 .…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Circular dichroism in molecular-frame photoelectron angular distributions in the dissociative photoionization ofH2andD2molecules

et al. 2014

Self Cite

View full text Add to dashboard Cite

The presence of net circular dichroism in the photoionization of nonchiral homonuclear molecules has been put in evidence recently through the measurement of molecular-frame photoelectron angular distributions in dissociative photoionization of H 2 [Dowek et al., Phys. Rev. Lett. 104, 233003 (2010)]. In this work we present a detailed study of circular dichroism in the photoelectron angular distributions of H 2 and D 2 molecules, oriented perpendicularly to the propagation vector of the circularly polarized light, at different photon energies (20, 27, and 32.5 eV). Circular dichroism in the angular distributions at 20 and to a large extent 27 eV exhibits the usual pattern in which inversion symmetry is preserved. In contrast, at 32.5 eV, the inversion symmetry breaks down, which eventually leads to total circular dichroism after integration over the polar emission angle. Time-dependent ab initio calculations support and explain the observed results for H 2 in terms of quantum interferences between direct photoionization and delayed autoionization from the Q 1 and Q 2 doubly excited states into ionic states (1sσ g and 2pσ u ) of different inversion symmetry. Nevertheless, for D 2 at 32.5 eV, there is a particular case where theory and experiment disagree in the magnitude of the symmetry breaking: when D + ions are produced with an energy of around 5 eV. This reflects the subleties associated to such simple molecules when exposed to this fine scrutiny.

show abstract

Section: Introductionsupporting

confidence: 81%

Section: Circular Dichroism For Photoemission In the Molecular Framementioning

confidence: 60%

Section: Introductionmentioning

confidence: 71%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Circular dichroism in molecular-frame photoelectron angular distributions in the dissociative photoionization ofH2andD2molecules

et al. 2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…In contrast to a 'typical' angularstreaking experiment in which time intervals are measured with attosecond resolution, ours is an energy-and angle-resolved measurement that determines the state of a system in the asymptotic limit of its time evolution. With respect to the measured asymmetric molecular-frame photoelectron angular distribution in a single symmetric synchrocyclotron pulse 18,19 , we observe asymmetric proton release in a single near-infrared multicycle circularly polarized pulse by tracking the electron localization in the molecular frame as a function of the laser phase at t i and the proton kinetic energy E k .…”

Section: Resultsmentioning

confidence: 99%

Understanding the role of phase in chemical bond breaking with coincidence angular streaking

Magrakvelidze

Schmidt

et al. 2013

Nat Commun

View full text Add to dashboard Cite

Electron motion in chemical bonds occurs on an attosecond timescale. This ultrafast motion can be driven by strong laser fields. Ultrashort asymmetric laser pulses are known to direct electrons to a certain direction. But do symmetric laser pulses destroy symmetry in breaking chemical bonds? Here we answer this question in the affirmative by employing a two-particle coincidence technique to investigate the ionization and fragmentation of H 2 by a long circularly polarized multicycle femtosecond laser pulse. Angular streaking and the coincidence detection of electrons and ions are employed to recover the phase of the electric field, at the instant of ionization and in the molecular frame, revealing a phase-dependent anisotropy in the angular distribution of H þ fragments. Our results show that electron localization and asymmetrical breaking of molecular bonds are ubiquitous, even in symmetric laser pulses. The technique we describe is robust and provides a powerful tool for ultrafast science.

show abstract

Angular Distributions in Molecular Photoionization

Lucchese

Dowek

2014

Attosecond and XUV Physics

View full text Add to dashboard Cite

Photoelectron angular distributions (PADs) in molecular photoionization can provide detailed information about the geometry of a molecule, the initial electronic state and the electronic state of the product molecular ion. In general, the molecular frame photoelectron angular distribution (MFPAD) can be a function of four angles for linearly and circularly polarized light and five angles for elliptically polarized light. In this chapter, we show how, for dipole transitions, these multidimensional distributions can be reduced to a limited number of one-dimensional functions. PADs must be determined relative to the molecular frame of reference and we consider experimental distributions that can be obtained with post-ionization analysis of the molecular frame orientation, using coincidence detection of the photoelectron and at least one ionic fragment. We also consider concurrent orientation, where a multiphoton process modifies the alignment of the molecule, helping the analysis of the PAD. And finally, we consider the form of the PAD when the molecule is preoriented, as can be achieved with impulsive alignment by intense infrared lasers. IntroductionThe ionization of molecules by absorption of light is significantly different from absorption where the final state is a bound state. In the case of ionization, the continuous nature of the final state leads to a lack of quantization for the total energy of the system. The infinite degeneracy of the continuum allows ejection of the photoelectron in any direction relative to the molecular frame (MF), that is, in any direction in the coordinate system of the molecule. The differential cross-section for this photoemission process is the molecular frame photoelectron angular distribution (MFPAD). This observable results from the coherent superposition of all partial waves contributing to the continuum electronic wavefunction: it therefore provides a very sensitive probe of the potentials and interactions governing the quantum dynamics of the emitted photoelectrons. In molecules, the MFPAD is a function of Attosecond and XUV Physics, First Edition. Edited by Thomas Schultz and Marc Vrakking.

show abstract

Circular Dichroism in Photoionization ofH2

Cited by 44 publications

References 31 publications

Circular dichroism in molecular-frame photoelectron angular distributions in the dissociative photoionization ofH2andD2molecules

Circular dichroism in molecular-frame photoelectron angular distributions in the dissociative photoionization ofH2andD2molecules

Understanding the role of phase in chemical bond breaking with coincidence angular streaking

Angular Distributions in Molecular Photoionization

Contact Info

Product

Resources

About