IT
Stunning discovery: a new state of matter identified between liquids and solids
According to recent research, a previously unknown, new state of matter may exist at the boundary between liquids and solids, as certain atoms remain stationary even in liquid metals. This discovery could fundamentally change how we understand the solidification and technological applications of metals.
With advances in technology, understanding the behaviour of materials under extreme conditions is becoming increasingly important. The transition of various metals from liquid to solid is a particularly crucial process, as it determines both the final material structure and its properties. A new study highlights that in this transitional region, a new state of matter can emerge, which is neither fully liquid nor conventionally solid.
A new state of matter at the atomic level
Researchers from the University of Nottingham in the UK and the University of Ulm in Germany investigated what happens to metals just before solidification, publishing their findings in the journal ACS Nano.
In their experiments, nanoparticles made of platinum, gold, and palladium were melted and then placed onto a thin graphene layer, which served both as a support and a heating surface. Transmission electron microscopy was used to study the molten metal nanodroplets as they gradually cooled.
When the metals melted, most atoms began to move rapidly as expected — exactly as one would anticipate from a liquid, since the bonding of particles changes during state of matter transitions.
However, the researchers observed a surprising phenomenon: some atoms in the liquid metal did not move, remaining stationary regardless of temperature, and began to attach themselves to a point defect in the graphene support. This behaviour is entirely different from what we previously understood about the atomic-level behaviour of liquids.
Formation of an “atomic corral”
According to Popular Mechanics, a key aspect of the research was that scientists were able to control the number of stationary atoms. By using an electron beam, they increased the number of defects in the graphene, allowing more stationary atoms and molecules to form within the liquid metal. The particles did not just remain isolated but could form ring-like structures — an “atomic corral” — around the liquid, which proved crucial for solidification.
When few stationary atoms were present, the liquid metal eventually crystallised into a solid. However, when many such atoms surrounded the liquid, crystallisation could be completely prevented, and the metal remained liquid well below its normal freezing point.
In the case of platinum nanoparticles, researchers observed that the liquid could maintain its liquid state of matter even at 350°C, over 1000 degrees lower than its normal freezing point. Since this state cannot be described as either a conventional liquid or a classic solid, the authors refer to it as a new state of matter.
Significance of the discovery
Interestingly, this new state of matter is not permanent. Over time, the liquid does eventually solidify, but not into a regular crystalline structure — rather, into an unstable, amorphous form. Once the “atomic corral” is disrupted or breaks down, the structure almost immediately transforms into a conventional crystal.
The researchers suggest that the practical implications of this discovery could be enormous. A better understanding of this new state of matter could contribute to more efficient use of rare-earth metals in energy conversion and storage, and improve the performance of carbon-based platinum materials.