Excitation and ionisation cross-sections in condensed-phase biomaterials by electrons down to very low energy: application to liquid water and genetic building blocks
| Autor: | Pablo de Vera, Isabel Abril, Rafael Garcia-Molina |
|---|---|
| Přispěvatelé: | Universidad de Alicante. Departamento de Física Aplicada, Interacción de Partículas Cargadas con la Materia |
| Rok vydání: | 2021 |
| Předmět: |
Models
Molecular Molecular Conformation FOS: Physical sciences General Physics and Astronomy Biocompatible Materials Electrons Applied Physics (physics.app-ph) 02 engineering and technology Electron 7. Clean energy 01 natural sciences Phase Transition Secondary electrons Physics - Chemical Physics Física Aplicada Ionization 0103 physical sciences Computer Simulation Physics - Biological Physics Physical and Theoretical Chemistry Born approximation 010306 general physics Electrons down Excitation Electron ionization Chemical Physics (physics.chem-ph) Ions Physics Condensed-phase biomaterials Range (particle radiation) Water Physics - Applied Physics DNA 021001 nanoscience & nanotechnology 3. Good health Computational physics Condensed Matter - Other Condensed Matter Liquid water Biological Physics (physics.bio-ph) Excited state RNA Thermodynamics Cross-sections 0210 nano-technology Genetic building blocks Other Condensed Matter (cond-mat.other) Ionisation |
| Zdroj: | RUA. Repositorio Institucional de la Universidad de Alicante Universidad de Alicante (UA) Physical Chemistry Chemical Physics |
| ISSN: | 1463-9084 1463-9076 |
| Popis: | Electronic excitations and ionisations produced by electron impact are key processes in the radiation-induced damage mechanisms in materials of biological relevance, underlying important medical and technological applications, including radiotherapy, radiation protection in manned space missions and nanodevice fabrication techniques. However, experimentally measuring all the necessary electronic interaction cross-sections for every relevant material is an arduous task, so it is necessary having predictive models, sufficiently accurate yet easily implementable. In this work we present a model, based on the dielectric formalism, to provide reliable ionisation and excitation cross-sections for electron-impact on complex biomolecular media, taking into account their condensed-phase nature. We account for the indistinguishability and exchange between the primary beam and excited electrons, for the molecular electronic structure effects in the electron binding, as well as for higher-order corrections to the first Born approximation. The resulting approach yields total ionisation cross-sections, energy distributions of secondary electrons, and total electronic excitation cross-sections for condensed-phase biomaterials, once the electronic excitation spectrum is known, either from experiments or from a predictive model. The results of this methodology are compared with the available experimental data in water and DNA/RNA molecular building blocks, showing a very good agreement and a great predictive power in a wide range of electron incident energies, from the large values characteristic of electron beams down to excitation threshold. The proposed model constitutes a very useful procedure for computing the electronic interaction cross-sections for arbitrary biological materials in a wide range of electron incident energies. 18 pages, 10 figures |
| Databáze: | OpenAIRE |
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