Scientists find new state of matter that allows atoms to exist as liquid and solid at the same time

'Recreating this unusual state in other materials could have all kinds of applications'

Scientists have found a new state of physical matter – which allows atoms to exist as both solid and liquid at the same time.

Atoms in physical material have been typically thought to be in one of three states: they were either solid, liquid, or they were gas. But researchers have discovered some elements that can take on properties of two different states, posing a complication to that view.

Scientists have not been sure whether those intermediate states were their own state of matter, or if they just represented a transition between the two.

New research clears up that dispute, and point to the fact that it is a distinct state of matter, known as "the chain-melted state". And now researchers hope it can be further examined to find more uses for the unexpected discovery.

Subjecting potassium to extreme environments – such as pushing it up against high pressures and temperatures – were combined with powerful computer simulations to allow scientists to study the unusual state.

They showed parts of both liquid and solid states. When subjected to those conditions, most of the elements formed into a lattice structure, of the kind that would be expected in a solid – but there was also a second set of atoms that were in a liquid arrangement.

The University of Edinburgh scientists in the study found that more than half a dozen other elements, including sodium and bismuth, were able to reach the state if they were put into the right environments.

Dr Andreas Hermann, of the university's School of Physics and Astronomy, led the study which is published in the journal Proceedings of the National Academy of Sciences.

He said: "Potassium is one of the simplest metals we know, yet if you squeeze it, it forms very complicated structures.

"We have shown that this unusual but stable state is part solid and part liquid.

"Recreating this unusual state in other materials could have all kinds of applications."

The study was supported by the European Research Council and the Engineering and Physical Sciences Research Council, and the work was carried out in collaboration with scientists from Xi'an Jiantong University in China.