Electron attachment to indole and related molecules
Alberto Modelli1, Derek Jones, Stanislav A Pshenichnyuk
1Dipartimento di Chimica "G. Ciamician", Universitá di Bologna, via Selmi 2, 40126 Bologna, Italy.
The Journal of Chemical Physics
|December 11, 2013
Summary
Low-energy electron attachment to indoline, indene, indole, and related compounds forms temporary negative ions. Dissociative electron attachment reveals hydrogen atom loss as a key fragmentation pathway, relevant to biochemical reactions.
Area of Science:
- * Physical Chemistry
- * Quantum Chemistry
- * Molecular Physics
Background:
- * Investigating electron interactions with organic molecules is crucial for understanding chemical reactivity.
- * Indole derivatives are prevalent in biologically significant molecules, necessitating studies on their electronic properties.
Purpose of the Study:
- * To investigate the gas-phase formation of temporary negative ion states in indoline, indene, indole, and related compounds.
- * To characterize the electronic structures and electron affinities of these molecules.
- * To explore dissociative electron attachment pathways and their relevance to biochemical processes.
Main Methods:
- * Electron Transmission Spectroscopy (ETS) for studying temporary negative ion states (0-6 eV).
- * Density Functional Theory (DFT) and Hartree-Fock calculations for virtual orbital energies.
- * Dissociative Electron Attachment Spectroscopy (DEAS) for fragment anion yields (0-14 eV).
Main Results:
- * First-time investigation of low-energy electron attachment to indoline, indene, indole, and derivatives.
- * Identified hydrogen atom loss ([M-H](-)) as the dominant fragmentation pathway in DEAS for compounds I-IV.
- * Calculated vertical and adiabatic electron affinities and thermodynamic thresholds for negative fragment production.
Conclusions:
- * Gas-phase electron attachment studies provide insights into molecular electronic structures.
- * DEAS data supports biochemical reaction mechanisms involving initial hydrogen abstraction from indole moieties.
- * Findings contribute to understanding the behavior of biologically relevant molecules in biological systems.
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