| Title: | Calculating Photoabsorption Cross-Sections for Atmospheric Volatile Organic Compounds |
| Author(s): | Prlj A; Marsili E; Hutton L; Hollas D; Shchepanovska D; Glowacki DR; Slavicek P; Curchod BFE; |
| Address: | "Department of Chemistry, Durham University, Durham DH1 3LE, U.K. Department of Physical Chemistry, University of Chemistry and Technology, Prague, Technicka 5, Prague 16628, Czech Republic. Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TH, U.K. ArtSci International Foundation, 5th Floor Mariner House, Bristol BS1 4QD, U.K. CiTIUS Intelligent Technologies Research Centre, Rua de Jenaro de La Fuente, s/n, Santiago de Compostela 15705, A Coruna, Spain" |
| DOI: | 10.1021/acsearthspacechem.1c00355 |
| ISSN/ISBN: | 2472-3452 (Print) 2472-3452 (Electronic) |
| Abstract: | "Characterizing the photochemical reactivity of transient volatile organic compounds (VOCs) in our atmosphere begins with a proper understanding of their abilities to absorb sunlight. Unfortunately, the photoabsorption cross-sections for a large number of transient VOCs remain unavailable experimentally due to their short lifetime or high reactivity. While structure-activity relationships (SARs) have been successfully employed to estimate the unknown photoabsorption cross-sections of VOCs, computational photochemistry offers another promising strategy to predict not only the vertical electronic transitions of a given molecule but also the width and shape of the bands forming its absorption spectrum. In this work, we focus on the use of the nuclear ensemble approach (NEA) to determine the photoabsorption cross-section of four exemplary VOCs, namely, acrolein, methylhydroperoxide, 2-hydroperoxy-propanal, and (microsolvated) pyruvic acid. More specifically, we analyze the influence that different strategies for sampling the ground-state nuclear density-Wigner sampling and ab initio molecular dynamics with a quantum thermostat-can have on the simulated absorption spectra. We highlight the potential shortcomings of using uncoupled harmonic modes within Wigner sampling of nuclear density to describe flexible or microsolvated VOCs and some limitations of SARs for multichromophoric VOCs. Our results suggest that the NEA could constitute a powerful tool for the atmospheric community to predict the photoabsorption cross-section for transient VOCs" |
| Notes: | "PubMed-not-MEDLINEPrlj, Antonio Marsili, Emanuele Hutton, Lewis Hollas, Daniel Shchepanovska, Darya Glowacki, David R Slavicek, Petr Curchod, Basile F E eng 2022/01/29 ACS Earth Space Chem. 2022 Jan 20; 6(1):207-217. doi: 10.1021/acsearthspacechem.1c00355. Epub 2021 Dec 17" |
