Physicists will study ozone formation and spectra
21.08.2019

A team of physicists from France, the USA, and Russia (TSU) is investigating the formation and decay of ozone and its characteristics and properties at the molecular level when interacting with radiation. The results will help to monitor the quality of the ozone layer, which is involved in forming the Earth’s atmosphere and climate, affects air quality, and protects the planet from strong ultraviolet radiation.

- Radiation can be absorbed or radiated by matter at the level of atoms, molecules, and their aggregates. The sun sends us ultraviolet radiation, which in small doses at relatively low frequencies gives us a tan, but at an increase in frequency is a deadly radiation that kills all life. The only molecule that protects us is ozone; if it did not, biological life on Earth would be impossible, - noted Vladimir Tyuterev, chief researcher at the Laboratory of Quantum Mechanics of Molecules and Radiation Processes of Tomsk State University, Professor at the University of Reims (France), chairperson of the program committee of the OZONE international conference. - This molecule has a number of paradoxical properties: the ozone layer at the top (in the stratosphere) is climate-forming and it protects us, but when ozone is formed in the lower layers of the atmosphere, it is part of urban smog, toxic to the human pulmonary system, activates compounds in the blood that provoke problems such as atherosclerosis, and creates environmental problems.

According to the scientist, constant remote sensing from satellites by spectral analysis methods is necessary for the most effective control of the content and evolution of ozone in the atmosphere. Every object has an absorption spectrum of radiation, and if it is expanded in wave frequency, then an alternation of peaks and dips will result. These results are individual for each molecule and atom, like fingerprints. If they are identified and decoded for ozone, then it is possible to remotely determine the presence of particles, their number, under what conditions they exist, at what temperature, and how it interacts. The problem is that the spectrum of ozone is difficult to accurately measure in laboratory conditions; because of its instability it may partially decay or react during the experiment.

- The ozone layer is a huge, dynamically changing mass. Hundreds of millions of tons of ozone are formed and destroyed daily in the atmosphere, but the properties of these masses determine the interaction of radiation with molecules at the quantum microlevel. Our task is to see what the spectra of ozone are and understand what helps us to control the process of its formation and decay, - said Vladimir Tyuterev.

The problems of the formation, decay, and evolution of ozone are a priority for many leading research centers. This is evidenced by the signing of the Montreal Protocol on its global control, but the key issues are related to the probabilities of molecular formation, isotopic anomalies not yet resolved. The breakthrough opportunities are associated with new methods of quantum theory of spectra and mathematical modeling using supercomputer clusters.

- Ozone consists of 3 oxygen atoms. When the sun illuminates the outer part of our atmosphere, which contains more than 20% oxygen, solar radiation breaks diatomic oxygen into atomic. The energy of ultraviolet radiation is released into kinetic energy, which leads to their intense collisions. At the same time, ozone formation is possible, - explained Vladimir Tyuterev. - Atomic oxygen is aggressive and immediately reacts when it collides with diatomic oxygen to form ozone. It has an equal choice of which of the two atoms to attach to, and the laws of quantum mechanics cannot say unambiguously to which one it will. From the point of view of the electronic structure, this atomic oxygen forms hybrid bonds in ozone. That is, the electron virtually jumps from one connection to another, resulting in a very unstable connection.

Physicists plan to measure the spectra of ozone, determine the details of its quantum structure in various energy states and its radiation properties in microwave and infrared radiation, and explain the formation of this molecule. The acquisition and processing of experimental spectra will be carried out in collaboration with the laboratories of the French National Center for Scientific Research (CNRS).