For the first time, a new type of molecule called the butterfly Rydberg molecule, was observed by physicists 14 years after it was predicted to exist. The discovery both proves a breakthrough in chemistry and confirms the existence of a new kind of atomic bond.
The findings published in Nature Communications by a team of researchers showed a peculiar type of molecule and its unconventional mechanism of binding. This weak pairing of two highly excitable atoms has defied the known rule of how atoms bind.
Butterfly Rydberg Molecule Gives New Chemistry Point of View
Rydberg molecules are electronically excited chemical species as it is formed when the electron is kicked far from the atom’s nucleus. Purdue’s Albert Overhauser Distinguished Professor of Physics and Astronomy Chris Greene and co-authors E. Hamilton and H. Sadeghpour theorized in 2002 that the Rydberg molecule can attract and bind to another atom at a very large distance.
The idea was not feasible at the time as it does not follow the rules of atom binding. So for the lab experiment, the researchers made use of a cooled down Rubidium gas with a 100 nano-Kelvin temperature that is a 10-millionth of a degree above absolute zero. They were able to create a Rydberg atom with the use of laser in separating the electron from its nucleus.
The atomic bond is considered unique as normally in atoms, it is only possibly to have a distance of one or two angstroms away from the electrons to the nucleus. Yet with the Rydberg atoms, it can reach up to “100 or 1,000 times away,” according to Greene.
Greene also adds the discovery provides a new “point of view of chemistry” when it comes to the atom’s binding mechanism with an electron binding and trapping an atom. The professor and the team are just satisfied to prove “this class of molecules exist.”
These butterfly Rydberg molecules are considerably larger than the normal molecules. The existence of this new atomic bond could make way for the development of molecular-sized machines that requires lesser energy.