If atoms did not connect to one another, everything we know would not exist. The Sun, the Earth, animals, plants, us — we are all based on that single chemical process when two atoms bond and form matter.
|SOURCE| And yet, as essential as this process is, scientists have never been able to record it on camera. That’s because chemical bonds occur on a really small scale — about half a million times smaller than the width of a human hair.
But thanks to the work of an international team of scientists, we are finally able to get a good glimpse of this intricate interaction at play.
The method — and video — is detailed in a paper published Friday in the journal Science Advances. This is the first time ever that scientists have been able to film the process in real time, according to the paper.
Filming atoms in real-time
The 18-second video shows two atoms bopping around separately in hollow cylinders of carbon. But slowly, they bop closer and closer together, before the two tiny specks suddenly merge as one. The unified figure then starts to distort, jumping about at different angles, and then, the bond is broken.
But, these two atoms can’t stay away from each other for too long. The pair rekindle their bond once more, and reform their everlasting molecule.
Filming atoms bonding with one another is a scientific feat that no one has been able to accomplish before. In order to capture the process, the scientists behind the footage trapped a pair of rhenium atoms — a type of heavy metal chemical element — within narrow nanotubes of carbon. These carbon cylinders have diameters at the molecular scale, between 1-2 nm, and were used as miniature test tubes for atoms.
The team then used transmission electron microscopy (TEM) to capture the process on film. TEM is a technique through which a high energy beam of electrons is used to visualize specimens and create an image.
“To our knowledge, this is the first time when bond evolution, breaking and formation was recorded on film at the atomic scale,” Andrei Khlobystov, professor at the University of Nottingham, and one of the lead authors of the study, said in a statement.
Why do atoms bond?
Atoms bond with one another in order to increase their stability and lower their energy. On their own, atoms exert more energy and are rather unstable. But once they combine, a positively charged and a negatively charged atom can form molecules with unique properties.
But to be able to bond, the atoms must first share electrons and achieve a balance between the positive and negative tug created by their nuclei and electrons.
As the video shows, the two atoms bond and walk together along the narrow hallways of the carbon test tubes. At one point, however, their bond snaps when the length of the bond exceeded the size of the atoms.
The bond between atoms changes as the environment around them changes. In this case, it became weaker as the atoms moved in a pair down the nanotubes, according to the study.
The two atoms became independent once again, but were pulled together shortly afterwards and reformed the molecule. Again, the attraction to bond is too great to resist — ultimately, the atoms exist in a more stable state and exert less energy as a pair. For us, and all other matter, that is just as well.