Scientists of Tomsk Polytechnic University jointly with their colleagues have synthetized a unique molecule of verdazyl-nitronyl nitroxide triradical. Only several research teams in the world were able to obtain molecules with similar properties. The molecule is stable. It is able to withstand high temperatures and obtains promising magnetic properties. It is a continuation of scientists' work on the search for promising organic magnetic materials. The research findings are published in the Journal of the American Chemical Society (IF: 14.612, Q1).
Magnetoresistive random-access memory (MRAM) is one of the most promising technologies for storage devices. Nowadays, the MRAM development is limited due to the fact it is impossible to create a smaller memory cell because of spontaneous magnetization reversal. Single-molecular magnets based on organic compounds are free from this disadvantage: few molecules are already capable to operate as a memory storage unit.
"At a certain temperature, a magnetic phase transition occurs, the consistent orientation of the magnetic vectors of molecules is observed, as a result, the matter becomes a united magnet. Thus, 20-40 molecules are quite enough to form a micromagnet.
Our task in the research laid in creation such a molecule that could be capable to give its magnetic properties at high temperatures, would be crystalline and would possess a small distance between radical centers,"
Pavel Petunin, Associate Professor of the TPU Research School of Chemistry and Applied Biomedical Sciences, an article author, explains.
When creating the molecule, the scientists worked with three radical centers in one molecule combined them in one conjugated structure. To synthetize the molecule, the scientists used a palladium-catalyzed reaction of a verdazyl radical with a gold complex of a nitronyl-nitroxyl radical. The course of the reaction was complicated due to the presence of unpaired electrons in starting compounds, as well as the combination of three radical centers in one molecule, which affects its stability. According to the scientists, there are no other ways to synthesize the molecule.
The research teams from TPU, the Vorozhtsov Novosibirsk Institute of Organic Chemistry of the Siberian Branch of Russian Academy of Sciences, the Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, the Voevodsky Institute of Chemical Kinetics and Combustion of the Siberian Branch of the Russian Academy of Sciences and International Tomography Center of the Siberian Branch of the Russian Academy of Sciences took part in the molecule synthesis. The research work was conducted within the project of the Russian Science Foundation No. 20-73-00236 "Stable Organic Radicals as Promising Building Blocks for New Materials".
"The published research not only makes a significant contribution to the development of stable verdazyl radicals but it is also a meaningful publication for TPU. Research teams of the TPU Research School of Chemistry and Applied Biomedical Sciences perfectly complete the mission, which was determined at the moment of the School creation. The Journal of the American Chemical Society is the most peer-reviewed chemical journal. Research teams around the globe are intending to publish their articles in this journal. It should be noted that it is a cycle of the research works of the research team. The authors have recently published their research work in the equally top-rated Angewandte Chemie academic journal (IF: 12.959, Q1)," Marina Trusova, Director of the TPU Research School of Chemistry and Applied Biomedical Sciences, says.
At the moment, the researchers have approached complicated molecules and are planning to synthetize almost impossible molecules: heterospin and high-spin dendrimers.