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arXiv · 1610.08234

Laser-Induced Electron Diffraction: Alignment Defects and Symmetry Breaking

T. T. Nguyen-Dang·M. Peters·J. Viau-Trudel·E. Couture-Bienvenue·R. Puthumpally-Joseph·E. Charron·O. Atabek
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Abstract

The fringe pattern that allows geometrical and orbital structure information to be extracted from LIED spectra of symmetric molecules is shown to reflect a symmetry conservation principle. We show that under a field polarization which preserves certain symmetry elements of the molecule, the symmetry character of the initial wave function is conserved during its time-evolution. We present a symmetry analysis of a deviation from a perfect alignment by decomposing the field into a major, symmetry-determining part, and a minor, symmetry breaking, part. This decomposition leads to a corresponding factorization of the time-evolution operator. The formalism is applied to the analysis of the robustness of LIED readings and inversions with respect to deviations from a perfect perpendicular and parallel alignment of a symmetric ABA triatomic molecule. The results indicate a particularly strong stability of the type of LIED spectra associated with the perpendicular alignment situation.

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T. T. Nguyen-Dang, M. Peters, J. Viau-Trudel, E. Couture-Bienvenue, R. Puthumpally-Joseph, E. Charron, O. Atabek. 2016-10-26. Laser-Induced Electron Diffraction: Alignment Defects and Symmetry Breaking. https://doi.org/10.1080/00268976.2017.1317858

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