A group of scientists from the University of Ulm (Germany) in the framework of the SALVE project recorded a video that has already been dubbed “the best short film of the year.” For the first time in history, researchers have been able to show how a bond is formed between two atoms – not schematically, but “live”, on real particles. And it was not a passive observation, but an experiment – the very fact of the recording and triggered the onset of the reaction.
The main instrument has become a transmission electron microscope, which works by analogy with a conventional camera. It only transmits not photons through a light-sensitive film, but electrons through ultra-thin samples of materials. The particles are so small that they made it possible to achieve unprecedented resolution – the video shows individual rhenium atoms with a diameter of 0.2 nanometers.
Scientists used a single-walled carbon nanotube about 1 nm wide as a “test tube”, a medium for connecting rhenium atoms. The choice of the material is due to the fact that although it belongs to heavy metals and has an atomic number of 75, its isotope is stable, and the sizes of atoms are “average”. The passage of an electron beam from a microscope gave them an energy impulse, which provoked the formation of an atomic rhenium-rhenium bond.
In addition to video recording, the experiment pursued a number of other goals. For example, scientists have proven that they can use an electron beam as a process control tool. And the shape of a carbon nanotube influences the behavior of atoms and makes it possible to create conditions for various modes of metal bond formation. Now the next step is to experiment with other metals and other scales.