Researchers from the Institute of astronomy of the Russian Academy of Sciences, the Ural Federal University and Moscow state University named after M. V. Lomonosov showed the dual role of photochemical processes in the formation of complex organic molecules in the interstellar medium. The authors showed that the intense ultraviolet radiation of massive stars destroys polyatomic molecules, preventing the development of complex molecules in unprotected areas, and the weak secondary radiation contributes to the creation of complex organic molecules in protected regions. About their work, the researchers reported in the journal “Successes of chemistry”.
“today, it is considered that the creation of complex molecules in the interstellar medium requires the formation of molecular radicals in interstellar ice through photolysis and radiolysis and the subsequent reactions between them, says co-author, head of the partner group of max Planck at the laboratory of extraterrestrial physics and astronomie Anim Urfu Anton Vasyunin. Is a complex multistage mechanism of these reactions, scientists began to investigate recently, and have yet to have a lot of tests to get a satisfactory understanding of astrogemini interstellar ice.”
In 1950-ies the scientists have suggested that space can cause a chemical reaction. Until the 1960s it was believed that in the gas phase of the interstellar medium can exist only simple molecules such as hydrogen and carbon monoxide. Astronomers assumed that the synthesis of more complex compounds in space almost not going because of low density and hard UV radiation.
Then came the tools that astronomers began to find molecules in space. Since the 1970s, each year researchers find four to five new molecules. Progress in this area of research has become faster with the invention of accurate infrared and radio telescopes.
The creators of the work decided to show how external factors, namely, high-energy electromagnetic radiation effect on the formation of complex organic molecules. It turned out that radiation has a dual impact on the process. On the one hand it can destroy unprotected molecules in the interstellar medium, and on the other to promote the formation of new compounds on the surface of the particles of cosmic dust.
The authors also showed that in astronomicheskii models of the interstellar medium must be included multistage processes and includes the physical adsorption of atoms and molecules from the gas phase of the interstellar medium, they drift on the surface of cosmic dust, heterogeneous catalysis, photolysis, radiolysis and desorption of final products, and the photochemical evolution of the dust grains themselves.
