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arXiv · 1609.06162

Averaged electron collision cross sections for thermal mixtures of $\alpha$-Alanine conformers in the gas phase

Milton M. Fujimoto·Erik V. R. de Lima·Jonathan Tennyson
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Abstract

A theoretical study of elastic electron collisions with 9 conformers of the gas-phase amino acid $\alpha$-alanine (CH$_3$CH(NH$_2$)COOH) is performed. The eigenphase sums, resonance features, differential and integral cross sections are computed for each individual conformer. Resonance positions for the low-energy $\pi^*$ shape resonance are found to vary from 2.6 eV to 3.1 eV and the resonance widths from 0.3 eV to 0.5 eV. Averaged cross sections for thermal mixtures of the 9 conformers are presented. Both theoretical and experimental population ratios are considered. Thermally-averaged cross sections obtained using the best theoretical estimates give reasonable agreement with the observed thermal cross sections. Excited conformers IIA and IIB make a large contribution to this average due to their large permanent dipole moments.

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Milton M. Fujimoto, Erik V. R. de Lima, Jonathan Tennyson. 2016-09-20. Averaged electron collision cross sections for thermal mixtures of $\alpha$-Alanine conformers in the gas phase. https://doi.org/10.1088/0953-4075/49/21/215201

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