This property (amongst others) makes it possible to exert a significant amount of control over radical reactants. As a result of having a magnetic dipole moment, arising from the spin of the unpaired electron(s), paramagnetic species in selected quantum states can be manipulated by external magnetic fields. It is apparent that, in order to accurately model the chemistry occurring in these (and other) complex and diverse gas-phase environments, we need to first understand the reactivity of key radical species.īeyond the direct applications to real-world gas-phase environments, studying the chemical reactions of radical species is also of fundamental interest. Many other radical species (such as OH, HO 2, C( 3P), and CH) are frequently formed as combustion by-products. 5,6 Molecular oxygen is typically paramagnetic, due to the triplet nature of the ground state, and is critical for combustion processes. 3 Many of the >240 molecular species unambiguously identified in interstellar regions are paramagnetic, 4 including the first molecule detected in the ISM, methylidyne (CH).
#Spacechem no thanks necessary free
1,2 The release of free Cl radicals upon the breakdown of chlorofluorocarbons by ultraviolet radiation in the stratosphere-resulting in the well-documented destruction of ozone-is another example of the important gas-phase chemistry driven by radical species. For example, OH has been described as the “vacuum cleaner” and the “detergent” of the troposphere, such is the ubiquity of hydroxyl radicals in atmospheric oxidation pathways. Indeed, radicals are directly responsible for much of the chemistry occurring in these complex gas-phase environments.
Paramagnetic species are important in a range of gas-phase processes: they are involved in reactions occurring in the atmosphere, in plasmas, in combustion systems, in flames, and in the interstellar medium (ISM). The research that Kathy, Chloé, and Brianna are conducting looks at how gas-phase reactions occur under cold and controlled conditions.ġ Introduction Atoms and molecules with one or more unpaired electrons in the outermost orbital are often referred to as ‘paramagnetic’ or ‘radical’ species. She relocated to the University of Liverpool in 2021. Brianna completed her undergraduate and PhD degrees at the University of Sydney, moving to the University of Oxford in 2012. Brianna Heazlewood is an EPSRC (Engineering and Physical Sciences Research Council) Early Career Fellow in the Department of Physics at the University of Liverpool. Chloé was awarded a BSc (2017) and MSc (2019) in Physical Chemistry and Chemical Physics from the University of Bordeaux, commencing her graduate studies at Oxford in October 2019. Kathy graduated from Oxford with an MChem degree in 2019 and gained an MSc in Computer Science from the University of Birmingham in 2020, returning to Oxford as a graduate student in October 2020. Lok Yiu (Kathy) Wu and Chloé Miossec are DPhil (PhD) students in the Department of Chemistry at the University of Oxford and Honorary Research Associates in the Department of Physics at the University of Liverpool. We conclude by identifying some of the limitations of current methods and exploring possible new directions for the field. We focus on low-energy reactive collisions involving neutral radical species, where the reaction parameters are controlled. In this highlight article, we explore some of the exciting recent developments in the study of chemical dynamics involving paramagnetic species. Coupled with ever-improving theoretical methods, quantum features are being observed and interesting insights into reaction dynamics are being uncovered in an increasingly diverse range of systems. Recent years have seen remarkable advances in the breadth of experimental methods successfully applied to the study of reaction dynamics involving paramagnetic species-from improvements to the well-known crossed molecular beams approach to newer techniques involving magnetically guided and decelerated beams. By controlling the properties of the colliding reactants, we can also gain insights into how radical reactions occur on a fundamental level.
As such, understanding how radicals react is essential for the development of accurate models of the complex chemistry occurring in these gas-phase environments. They are prevalent in the atmosphere, in interstellar space, and in combustion processes. Radicals are abundant in a range of important gas-phase environments.