Welcome to Prof. Matti Rissanen's

Radical Aerosol Physical Chemistry Group

Tampere & Helsinki Universities, Finland

RAPC group is working hard to keep the Earth a habitable space also in the future. Our keenest focus is on rapid chain-like chemical reactions in the gas-phase that are critical for the generation, but also decay, of air pollutants. These sequences are particularly important for atmospheric particulate matter production, and notwithstanding their importance for our health and the climate, their formation paths keep eluding the researchers. A cornerstone of our research is chemical ionization development, which we strive to make the comprehensive detection method across all media and phases.


Research Themes

Making Chemical Ionization Mass Spectrometry (CIMS) a chemically selective, versatile, and unrivaled detection method across all media and phases

What we do: Joint computational-experimental research investigating the molecular-level interactions between select reagent ions and molecular targets. We use quantum chemical computations to inspect the ion-molecule reaction mechanisms with focus on the adducting patterns and strength. Complementary laboratory investigations are performed whenever feasible, mainly applying a collection of flow reactor setup. An important aim is to supply a pool of new, previously unused, reagent ion chemistries, and construct a multi-ion scheme that can be used for a comprehensive gas-phase detection methodology. Tightly coupled with these aims is the related instrument development.

Let me ask you: What research would not benefit from a comprehensive detection methodology by a single research instrument?

Resolving the molecular mechanisms of complex oxidation networks resulting in atmospheric particulate matter formation

What we do: Comprehensive molecular-level oxidation mechanism investigations applying complementary theoretical and experimental methods. While the group’s focus is centered on rapid radical reactions that are best studied in short time-scale flow reactor setups applying the multi-ion CIMS platform (i.e., TD-MION-MS), the vast spatial and temporal scales of the new particle formation (NPF) phenomena necessitate gathering observations from various sources. Thus, the group regularly participates in ambient field deployments and environmental chamber campaigns organized in various locations around the globe, and part-takes in research consortia aimed to generate large scale air quality models.

Consider that: The enormous complexity of molecular-level atmospheric particulate matter formation requires a multifaceted approach that considers everything between molecular sizes from below one nanometer to particle sizes of several micrometers, to spatial scales from meters to hundreds of kilometers, and timescales from pico-seconds to decades. While this research was, in some sense, initiated already in the 1860’s, it’s remarkably how little we know about the details of the molecular processes even now in the 2020’s.

Quantifying the state of the environment and public health by rapid non-intrusive, non-invasive CIMS analysis

Air pollution and climate change, chemicalization of the environment and the shortage of drinking water, and the related consequences to population health are threatening the well-being, and even the existence of our society. The same gas-phase detection techniques can be used for inferring the state of any ecosystem, and our aim is to learn to interpret the data rich signals correctly. Health is assessed preferably by breath analysis, but also from other body metabolites like saliva or tear drops.

What we do: Develop research methodologies and workflows for more efficient and cheaper, high throughput analysis routines that can be applied to gauge the environment and human health by a rapid CIMS analysis. Our research targets, for example, faster and softer volatilization techniques and methods of using smaller sample volumes.

Think about it: If you hear the bad news almost daily, what do you think the future has stored for us? Is it reasonable to assume the silver-lining when we have characterized only a mere fraction of the processes, their linkages, and feedbacks? Is the glass half-full, or should it be fixed before all has leaked out?