For the first time, two metal atoms that bind and break are captured on the image.

Atoms are the building blocks of the world. Everything around us is based on that one chemical process in which two atoms bond and form matter. Yet researchers still know little about how and why atoms bond together. A research team wanted to change that. And successfully. In a new study I succeeded in making a video for the first time showing how a chemical compound is formed.


Whether it is a molecule (which is made up of atoms linked together in a fixed arrangement of chemical compounds), or a complete living organism: in the end everything is determined by the way atoms bond and the way bonds bond. However, this is very difficult to understand. Namely, the length of chemical compounds is between 0.1 and 0.3 nanometers, or; about half a million times smaller than the width of a human hair. This makes it almost impossible to directly observe the bond between a few atoms.

Rhenium atoms

However, a new research team was not dismayed. They decided to make the impossible possible and decided to create a groundbreaking video showing how atoms bond together. A true first: this has never happened before. To capture the process, the researchers trapped a few rhenium atoms – a type of heavy metal chemical element – in narrow carbon nanotubes. These are very small thin, hollow carbon cylinders that serve as test tubes for the atoms. “Nanotubes help us to capture atoms or molecules and place them exactly where we want them,” explains researcher Andrei Khlobystov. “In this case we chose rhenium atoms. That’s because this atom is easier to see than lighter elements, allowing us to recognize each metal atom as a dark dot. ”

Above you can watch the special movie. The 18-second video shows how two atoms hop around, then come closer together with slow thrusts and eventually merge. That only takes a while. The dot jumps around a bit before the connection is broken again. Moments later, the atoms come together again to form the Re2 molecule. “It was surprising how the two atoms move, which clearly indicates a bond between the two,” said researcher Kecheng Cao. “It is important that when Re2 moves down the nanotube, the bond length changes. This indicates that the bond becomes stronger or weaker, depending on the environment around the atoms. ”

Metal atoms

Connections between metal atoms are very important in chemistry, especially for understanding the magnetic, electrical or catalytic properties of materials. What makes it such a challenge, however, is that transition metals – such as Re – can form compounds with different sequences; from single to quintuple connections. In the current experiment, the researchers found that the two rhenium atoms are primarily linked via a quadruple bond, providing new fundamental insights into the chemistry of transition metals.

The short video is an exceptional achievement. “As far as we know, this is the first time that the confluence, breaking, and bonding has been recorded on video at an atomic scale,” said Khlobystov. “We are pushing boundaries and are increasingly entering the dynamics of individual molecules real time understand.”