Historic breakthrough: Discovery of one‑electron covalent bond by Tokyo scientists
According to information from the scientific journal Nature, a covalent bond that requires only a single electron is the first new type of chemical bond to be discovered in over ten years. Scientists at the University of Tokyo can, therefore, boast of a historic discovery.
Covalent bonds are those in which atoms share electrons. Until now, known bonds of this type required two, four, or six electrons.
A covalent bond utilising just one electron was predicted as early as 1931 by the eminent scientist Linus Pauling, an American chemist and physicist who won two Nobel Prizes — in Chemistry (1954) and the Nobel Peace Prize (1962). However, it is only now, after several decades, that such a bond has been created between carbon atoms.
As reported in "Nature," Prof. Takuya Shimajiri from the University of Tokyo and his team have been studying chemical bonds for years. Their earlier work focused on exceptionally long and flexible bonds. This time, the Japanese scientists used a chemical reaction (oxidation) to remove an electron from an existing two-electron covalent bond between two carbon atoms.
A large hydrocarbon molecule was used to stabilise the exceptionally long bonds between the carbon atoms because replacing the removed electron with another electron from the molecule would be energetically costly.
Extraordinary discovery by Japanese scientists
Previous attempts to remove electrons led to the formation of weak, quickly disintegrating bonds that did not allow for thorough chemical analysis. The molecule used by the team behind this success was sufficiently stable to perform analysis utilising X-ray radiation and several types of light.
The manner in which the radiation was reflected or absorbed demonstrated that it is a stable one-electron bond. According to experts, the discovery could lead to the creation of entirely new families of molecules.
Now, Prof. Shimajiri intends to investigate how one-electron covalent bonds can alter chemical reactions. He and his collaborators also want to clarify what a covalent bond actually is, since it can look different from what was previously assumed.
