A top Kiwi scientist has helped characterise an intriguing and relatively new chemical element, which had proven a headache to study.

First synthesised as a single atom in 2002 at the Joint Institute for Nuclear Research (JINR) in Russia, oganesson, or Og, is the only noble gas which doesn't naturally occur and must be synthesised in experiments.

Widely known as Element 118, Og is also one of only two elements to be named after a living scientist, nuclear physicist Yuri Oganessian.

However, studying one of the heaviest elements with the highest atomic number to ever be synthesised - 118 - has been no easy task.


Oganesson is radioactive and extremely unstable with a half-life of less than a millisecond, making it impossible to examine by chemical methods.

This meant computing its electronic structure is the next best thing, which was in itself a formidable task.

Teams led by Massey University's Distinguished Professor Peter Schwerdtfeger, of the New Zealand Institute for Advanced Study, and nuclear physicist Witold Nazarewicz of Michigan State University in the US, were able to make the calculations.

"Calculations are the only way to get at its behaviour with the tools that we currently have, and they have certainly provided some interesting findings," Schwerdtfeger said.

The work suggests that oganesson electrons weren't confined to distinct orbitals and are distributed evenly.

Massey University's Distinguished Professor Peter Schwerdtfeger. Photo / Supplied
Massey University's Distinguished Professor Peter Schwerdtfeger. Photo / Supplied

"On paper, we thought that it would have the same rare gas structure as the others in this family.

"In our calculations however, we predict that oganesson more or less loses its shell structure and become a smear of electrons."

Further, it was thought to be a gas under normal conditions, but is now predicted to be a solid according to newest research from the Massey group.

"Oganesson is quite different to the other rare gas atoms, as its shells are barely visible in an electron localisation function plot and has been smeared to near-invisibility," Schwerdtfeger added.

"Oganesson comes quite close to the limiting case of a Fermi gas."

The team also calculated the structure of protons and neutrons inside the nucleus, which indicated a smeared-out structure for the neutrons as well.

The protons however retained some shell-like ordering.

Schwerdtfeger is one of the world's leading theoretical chemists, winning New Zealand's highest honour in science, the Rutherford Medal, in 2014, and remaining the most highly cited chemist and physicist in the country at his age.

His multi-disciplinary research has provided a deep insight into how atoms and molecules interact at the quantum level.