A research team from the National Institute for Materials Science (NIMS), Osaka University, and Kanazawa University has successfully controlled the chirality of individual molecules through structural isomerization for the first time. This was achieved using a scanning tunneling microscope probe at low temperatures. The team also synthesized highly reactive diradicals with two unpaired electrons. The technique could be used to create novel carbon nanostructures and quantum materials. The research was published in Nature Communications.
Groundbreaking Achievement in Molecular Control
An international team of researchers from the National Institute for Materials Science (NIMS), Osaka University Graduate School of Science, and the Kanazawa University Nano Life Science Institute (WPI-NanoLSI) has made a significant breakthrough in molecular science. For the first time, they have managed to control the chirality, or ‘handedness,’ of individual molecules through a process known as structural isomerization. This achievement marks a significant step forward in the understanding and manipulating molecular structures.
The team also successfully synthesized highly reactive diradicals, molecules with two unpaired electrons. This is a notable accomplishment as diradicals are typically highly reactive and difficult to synthesize in organic chemistry. The ability to create and control these molecules opens up new possibilities for investigating their electronic and magnetic properties.
Innovative Technique for Molecular Manipulation
The researchers developed a novel technique to alter the chirality of specific individual molecular units within a three-dimensional nanostructure. This was achieved by exciting a target molecular unit with a tunneling current from a scanning tunneling microscope probe under ultrahigh vacuum conditions at low temperatures.
By precisely controlling the parameters of current injection, such as the molecular size and the applied voltage, the team could rearrange molecular units into three different configurations: two different stereoisomers and a diradical. This level of control and precision in molecular manipulation is unprecedented and demonstrates the potential of this technique for further applications in molecular science.
Demonstrating Control and Reproducibility
The team demonstrated the controllability and reproducibility of their technique by encoding ASCII characters using binary and ternary values in a series of one-dimensional molecular arrays. Each array represented a single character, spelling out “NanoProbe Grp. NIMS©”. This demonstration not only showcases the precision of the technique but also its potential for practical applications in data storage and manipulation at the molecular level.
Future Applications and Research
The research team plans to use this structural isomerization technique to fabricate novel carbon nanostructures composed of designer molecular units. The ability to control the configurations of these units opens up exciting possibilities for the creation of new materials with tailored properties.
In addition, the team will explore the potential for creating quantum materials. These are materials in which radical molecular units lead to magnetic exchange couplings between the units, a quantum mechanical effect. This could have significant implications for the development of quantum computing and other advanced technologies.
Acknowledgements and Publication
The research was carried out by a team led by Shigeki Kawai of NIMS, with contributions from researchers at Osaka University and Kanazawa University. The work was partly supported by the Japan Society for the Promotion of Science, the Academy of Finland, and the World Premier Internal Research Center Initiative in Japan. The findings were published in the November 25, 2023 issue of Nature Communications. Key researchers include Shigeki Kawai, Zhangyu Yuan, Kewei Sun, Oscar Custance, Takashi Kubo, and Adam S. Foster.
