Revisiting the Absorption Spectra of Polycyclic Aromatic Hydrocarbons over Porto (Portugal) by TD-DFT Calculations

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Fernandes, GM (Author) Other; Macedo, FJD (Author) Other; Joaquim C G E Esteves da Silva (Author) FCUP; da Silva, LP (Author) FCUP

Journal

The Journal is awaiting validation by the Administrative Services.

Title: SUSTAINABLE CHEMISTRY

Pages: 511-519

ISSN: 2673-4079

Associated Projects

CIQUP - Financiamento Plurianual da Unidade de I&D CIQUP - Centro de Investigação em Química da Universidade do Porto

Other information

Authenticus ID: P-00X-HZJ

DOI: 10.3390/suschem3040031

Abstract (EN): <jats:p>Brown carbon is a type of strong light-absorbing carbonaceous aerosol associated with radiative forcing. Nevertheless, the difficulty in correlating the chemical composition of brown carbon with its light absorption properties impairs the proper elucidation of its role in radiative forcing. Here, we have used a time-dependent density functional theory (TD-DFT)-based procedure to revisit the ¿real-world¿ absorption spectra of polycyclic aromatic hydrocarbons (PAHs) over the city of Porto, in Portugal, while correcting the spectra for their quantity in PM10 particulate matter. Our aim is to, by comparing these new results with those obtained previously regarding PM2.5 data, evaluate the role of different groupings of particulate matter in the light absorption of brown carbon. The results indicate that irrespective of the absorption spectra corresponding to their PM10 or PM2.5 data, the studied PAHs should contribute to radiative forcing by light absorption at UVA and (sub)visible wavelengths. However, the identity of the individual PAH species that contribute the most for the considered wavelengths can be quite different. Thus, different groupings of particulate matter appear to provide distinct contributions to light absorption and radiative forcing over the same location, even when considering the same class of molecular compounds.</jats:p>

Language: English

Type (Professor's evaluation): Scientific