Did you know that tiny droplets of water in the atmosphere can transform a common air pollutant into powerful climate-warming compounds? In this episode of Papers Illuminated – Člankarnica, we sit down with Kristijan Vidović from the Department of Analytical Chemistry to explore the hidden chemistry taking place inside clouds, rain, fog, and atmospheric aerosol particles.

Our conversation focuses on his latest research, published in Environmental Science & Technology, investigating how naphthalene reacts in the atmospheric aqueous phase under sunlight and in the presence of HONO. Rather than producing the compound scientists traditionally expected, the study reveals that the dominant product under atmospherically relevant conditions is 2-nitro-1-naphthol, a previously unrecognized contributor to brown carbon. A second product, 1-nitronaphthalene, appears mainly under more concentrated conditions associated with aerosol liquid water.

We discuss what brown carbon is, why its ability to absorb sunlight matters for both air quality and climate, and how water, hydroxyl radicals, dissolved oxygen, and HONO work together to drive these atmospheric reactions. Kristijan also explains how the team combined laboratory experiments, HPLC and mass spectrometry, UV–Vis spectroscopy, kinetic modeling, and thermochemical calculations to reconstruct the reaction mechanism and estimate the climate relevance of these compounds.

Join us for a fascinating journey into the chemistry of the atmosphere, where invisible gases, sunlight, and microscopic water droplets interact to influence the air we breathe, the formation of particles, and the planet’s radiative balance. Along the way, Kristijan shares insights from his scientific journey, the importance of persistence and curiosity in research, the surprising power of simple analytical tools, and his dream experiment: monitoring particle formation around Ljubljana to better understand the unique atmospheric chemistry taking place in Slovenia.

You can read the whole paper here: https://pubs.acs.org/esthag/article/60/23/16758/5184061/Integrated-Kinetic-and-Thermochemical-Analysis-of