Imaging molecular geometry with electron momentum spectroscopy

Wang, Enliang; Shan, Xu; Tian, Qiguo; Yang, Jing; Gong, Maomao; Tang, Yuchao; Niu, Shanshan; Chen, Xiangjun

doi:10.1038/srep39351

Cited by 9 publications

(4 citation statements)

References 49 publications

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“…The vertical ionization potentials of the three outermost 1π g , 1π u , and 3σ u orbitals are 13.8 eV, 17.6 eV, and 18.1 eV, respectively [43,44]. Here we study ionization of an electron from one of these orbitals which will lead to stable nondissociating CO 2 + in the ionic states X 2 Π g , A 2 Π u , and B 2 Σ u , respectively.…”

Section: The Co 2 Targetmentioning

confidence: 99%

Triple-differential cross sections for single ionization of CO₂ by 100 eV electron impact

Hossen

Ren

Wang

et al. 2018

J. Phys. B: At. Mol. Opt. Phys.

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We present a combined experimental and theoretical study for electron-impact ionization of carbon dioxide (CO 2 ) for the projectile energy E 0 =100 eV. Experimental triple-differential cross sections (TDCS) are obtained using a multi-particle momentum spectrometer (reaction microscope). For projectile scattering angles between −5°and −20°a large part of the full solid angle is covered for the slow ejected electron with energies between 5 and 15 eV. The experimental data are measured for the ionization of the three outer valence molecular orbitals 1π g , 1π u , and 3σ u which lead to a non-dissociating CO 2 + ion. The measured TDCS summed over all three orbitals are internormalized across the scattering angles and ejected electron energies. They are compared to the theoretical results from the multi-center distorted wave (MCDW) approximation, and from the MCDW-WM approximation which includes post-collision interaction using the Ward-Macek factor (WM). Reasonable good agreement is found between the experiment and the MCDW-WM calculations for the angular dependence and the relative magnitude of the cross sections in the coplanar plane, while for the perpendicular and full perpendicular planes larger discrepancies exist. Since post-collision interaction is not considered the MCDW method shows strong discrepancies with experiment for small mutual angles of the two outgoing electrons in the final state.electron impact, ionization, kinematically complete (e, 2e) experiment, CO 2 , MCDW

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Section: The Co 2 Targetmentioning

confidence: 99%

Triple-differential cross sections for single ionization of CO₂ by 100 eV electron impact

Hossen

Ren

Wang

et al. 2018

J. Phys. B: At. Mol. Opt. Phys.

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“…Interestingly, MCTDW predicts more accurate oscillation structures at high momenta than PWIA for these fluorine 2p lone pair orbitals. These oscillation structures, usually referred to as bond oscillations, ,,− can be regarded as the interference of the outgoing electron ionized from the indistinguishable multi-atomic centers. The outgoing wave function will be distorted in the multicenter ionic (or neutral) molecular potentials, leading to some shrinking of the bond oscillation structures as compared to the plane wave description.…”

Section: Resultsmentioning

confidence: 99%

Experimental and Theoretical Study on Electron Momentum Spectroscopy of SF₆: Distorted-Wave and Vibrational Motion

et al. 2023

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The vibrational and distorted-wave effects are usually invoked to explain the measured electron momentum profiles for molecular orbitals. The vibrational effect can be accounted for quantitatively by a harmonic analytical quantum mechanical approach within the plane-wave impulse approximation (PWIA). On the other hand, quantitative calculation considering the distorted-wave effect was available only recently by a multicenter-threedistorted-wave (MCTDW) method (Phys. Rev. A2022, 105, 042805). Here, we report a joint experimental and theoretical investigation on electron momentum spectroscopy of SF 6 . The experiments were performed using a high-sensitivity (e, 2e) spectrometer employing noncoplanar symmetric geometry with incident electron energy equal to 1200 eV + binding energy. The experimental electron momentum profiles are compared with theoretical calculations by the MCTDW method at equilibrium geometry and by the PWIA method both at equilibrium geometry and considering vibrational motions. For all the measured orbitals, large discrepancies were observed between the experiments and the PWIA calculations at equilibrium geometry. For the highest occupied molecular orbital 1t 1g , the vibrational effect can partly explain the high intensity of the experimental momentum profile at low momenta. For the other orbitals, the influence of the vibrational effect is negligible. On the other hand, the MCTDW calculations improve the agreement with the experiments for all the observed orbitals, indicating that the distorted-wave effect plays an important role in reproducing the measured momentum profiles of SF 6 .

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“…and the three outermost (2t 1 , 7t 2 , 2e) orbitals of CCl 4 [14] were conducted. In parallel, bond oscillation was used for the purpose of obtaining molecular structural information and tested for CO 2 and CF 4 [15] and propane [16]. Clearly, molecular targets and MOs studied are still scarce and further investigations are required to develop and enhance the potential ability of bond oscillation.…”

Section: Introductionmentioning

confidence: 99%

A comparative study of interference effects in (e, 2e) electron momentum profiles of CO₂, ethylene and 1,3-butadiene

Isao¹,

Yamazaki²,

Takahashi³

2019

J. Phys. B: At. Mol. Opt. Phys.

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We report a comparative (e, 2e) study of intereference effects in the spherically-averaged electron momentum density distributions of the outermost orbitals of CO2, ethylene and 1,3-butadiene. The experiments on the three molecular orbitals, being each composed of 2p atomic orbitals, were performed in the symmetric noncoplanar geometry and at an incident electron energy of 1.2 keV. Interference patterns have then been obtained for each molecular orbital by dividing the experimental data by (e, 2e) cross section of a 2p atomic orbital calculated by using distorted wave impulse approximation. It is clearly demonstrated that interference patterns tell about constructive or destructive nature of the overlap between the constituent 2p atomic orbitals. Furthermore, it is shown that higher instrumental momentum resolution would be required for detailed studies on interference effects in cases when two of the constituent atomic orbitals with larger spatial separation are both oriented perpendicular to the molecular axis or plane.

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Imaging molecular geometry with electron momentum spectroscopy

Cited by 9 publications

References 49 publications

Triple-differential cross sections for single ionization of CO₂ by 100 eV electron impact

Triple-differential cross sections for single ionization of CO₂ by 100 eV electron impact

Experimental and Theoretical Study on Electron Momentum Spectroscopy of SF₆: Distorted-Wave and Vibrational Motion

A comparative study of interference effects in (e, 2e) electron momentum profiles of CO₂, ethylene and 1,3-butadiene

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Imaging molecular geometry with electron momentum spectroscopy

Cited by 9 publications

References 49 publications

Triple-differential cross sections for single ionization of CO2 by 100 eV electron impact

Triple-differential cross sections for single ionization of CO2 by 100 eV electron impact

Experimental and Theoretical Study on Electron Momentum Spectroscopy of SF6: Distorted-Wave and Vibrational Motion

A comparative study of interference effects in (e, 2e) electron momentum profiles of CO2, ethylene and 1,3-butadiene

Contact Info

Product

Resources

About

Triple-differential cross sections for single ionization of CO₂ by 100 eV electron impact

Triple-differential cross sections for single ionization of CO₂ by 100 eV electron impact

Experimental and Theoretical Study on Electron Momentum Spectroscopy of SF₆: Distorted-Wave and Vibrational Motion

A comparative study of interference effects in (e, 2e) electron momentum profiles of CO₂, ethylene and 1,3-butadiene