Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications
Photoelectron circular dichroism (PECD) is an intense orbital-specific chiroptical effect observed as asymmetries in the angular distribution of photoelectrons produced by photoionization of randomly oriented pure enantiomers with circularly polarized light. After a broad introduction placing this e...
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| Format: | Article |
| Language: | English |
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Taylor & Francis Group
2018-01-01
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| Series: | Advances in Physics: X |
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| Online Access: | http://dx.doi.org/10.1080/23746149.2018.1477530 |
| _version_ | 1818041540670390272 |
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| author | Rim Hadidi Dusan K. Bozanic Gustavo A. Garcia Laurent Nahon |
| author_facet | Rim Hadidi Dusan K. Bozanic Gustavo A. Garcia Laurent Nahon |
| author_sort | Rim Hadidi |
| collection | DOAJ |
| description | Photoelectron circular dichroism (PECD) is an intense orbital-specific chiroptical effect observed as asymmetries in the angular distribution of photoelectrons produced by photoionization of randomly oriented pure enantiomers with circularly polarized light. After a broad introduction placing this effect in the context of new physical chiral-sensitive methods, we review the main characteristics of PECD in terms of molecular photoionization dynamics. We stress also the analytical capabilities of PECD to retrieve enantiomeric excesses (e.es.) and to probe subtle details of the whole molecular potential, some of them exemplified by the showcase camphor and fenchone molecules. We then present the case of the amino acid alanine for which an interplay between PECD and conformer population is rationalized. Based on this study, we propose a photophysical astrophysical scenario for the origin of life’s homochirality, relying upon the asymmetry of the associated recoiling alanine parent ion that could lead at the relevant Lyman-α energy to an e.e. of up to 4% in a given line of sight, which appears independent of the temperature. In an attempt to generalize this scenario to other amino acids, new data on proline showing an e.e. of 12%, of the same sign as alanine, are also presented. Abbreviations ARPES: Angle-resolved photoemission; CMS-Xa: Continuum multiple scattering with Xa local-exchange potential; CPL: Circularly polarized light; CD: Circular dichroism; CSM: Circumstellar medium; DPI: Dissociative ionization; HHG: High harmonics generation; HOMO: Highest occupied molecular orbital; ISM: Interstellar medium; KE: Kinetic energy; MS: Mass spectrometry; MW: Microwave; PAD: Photoelectron angular distribution; PECD: Photoelectron circular dichroism; PECD-PICO: Photoelectron circular dichroism / photoion coincidence; PEPICO: Photoelectron / photoion coincidence; PES: Photoelectron spectrum; PV: Parity Violation; REMPI: Resonance-enhanced multi-photon ionization; RH: Resistive heating; TD: Thermodesorption; UV: Ultra-violet; VMI: Velocity map imaging; VUV: Vacuum ultra-violet. |
| first_indexed | 2024-12-10T08:32:03Z |
| format | Article |
| id | doaj.art-0a6b15e0b2de4fd68324f4aac7d83620 |
| institution | Directory Open Access Journal |
| issn | 2374-6149 |
| language | English |
| last_indexed | 2024-12-10T08:32:03Z |
| publishDate | 2018-01-01 |
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| spelling | doaj.art-0a6b15e0b2de4fd68324f4aac7d836202022-12-22T01:56:04ZengTaylor & Francis GroupAdvances in Physics: X2374-61492018-01-013110.1080/23746149.2018.14775301477530Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implicationsRim Hadidi0Dusan K. Bozanic1Gustavo A. Garcia2Laurent Nahon3L’Orme des MerisiersL’Orme des MerisiersL’Orme des MerisiersL’Orme des MerisiersPhotoelectron circular dichroism (PECD) is an intense orbital-specific chiroptical effect observed as asymmetries in the angular distribution of photoelectrons produced by photoionization of randomly oriented pure enantiomers with circularly polarized light. After a broad introduction placing this effect in the context of new physical chiral-sensitive methods, we review the main characteristics of PECD in terms of molecular photoionization dynamics. We stress also the analytical capabilities of PECD to retrieve enantiomeric excesses (e.es.) and to probe subtle details of the whole molecular potential, some of them exemplified by the showcase camphor and fenchone molecules. We then present the case of the amino acid alanine for which an interplay between PECD and conformer population is rationalized. Based on this study, we propose a photophysical astrophysical scenario for the origin of life’s homochirality, relying upon the asymmetry of the associated recoiling alanine parent ion that could lead at the relevant Lyman-α energy to an e.e. of up to 4% in a given line of sight, which appears independent of the temperature. In an attempt to generalize this scenario to other amino acids, new data on proline showing an e.e. of 12%, of the same sign as alanine, are also presented. Abbreviations ARPES: Angle-resolved photoemission; CMS-Xa: Continuum multiple scattering with Xa local-exchange potential; CPL: Circularly polarized light; CD: Circular dichroism; CSM: Circumstellar medium; DPI: Dissociative ionization; HHG: High harmonics generation; HOMO: Highest occupied molecular orbital; ISM: Interstellar medium; KE: Kinetic energy; MS: Mass spectrometry; MW: Microwave; PAD: Photoelectron angular distribution; PECD: Photoelectron circular dichroism; PECD-PICO: Photoelectron circular dichroism / photoion coincidence; PEPICO: Photoelectron / photoion coincidence; PES: Photoelectron spectrum; PV: Parity Violation; REMPI: Resonance-enhanced multi-photon ionization; RH: Resistive heating; TD: Thermodesorption; UV: Ultra-violet; VMI: Velocity map imaging; VUV: Vacuum ultra-violet.http://dx.doi.org/10.1080/23746149.2018.1477530Photoelectron circular dichroismphotoionizationhomochiralityalanineproline |
| spellingShingle | Rim Hadidi Dusan K. Bozanic Gustavo A. Garcia Laurent Nahon Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications Advances in Physics: X Photoelectron circular dichroism photoionization homochirality alanine proline |
| title | Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications |
| title_full | Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications |
| title_fullStr | Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications |
| title_full_unstemmed | Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications |
| title_short | Electron asymmetries in the photoionization of chiral molecules: possible astrophysical implications |
| title_sort | electron asymmetries in the photoionization of chiral molecules possible astrophysical implications |
| topic | Photoelectron circular dichroism photoionization homochirality alanine proline |
| url | http://dx.doi.org/10.1080/23746149.2018.1477530 |
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