New Material Defies Laws of Physics by Expanding When Squeezed

When you squeeze something, it usually gets smaller. You can compress a sponge, for example, or ball up a piece of paper. Now it seems that scientists have defied these laws of physics, creating a new material that expands when it's squeezed.

"It's like squeezing a stone and forming a giant sponge," said Karena Chapman, a chemist at the U.S. Department of Energy laboratory, in a news release. "Materials are supposed to become denser and more compact under pressure. We are seeing the exact opposite. The pressure-treated material has half the density of the original state. This is counterintuitive to the laws of physics."

In order to accomplish this feat, the scientists put zinc cyanide, a material used in electroplating, in a diamond-anvil cell. They then applied high pressures to this material--about 9,000 to 18,000 times the pressure of the atmosphere at sea level. The material actually rearranged under pressure, forming new bonds and creating pores.  By using different fluids around the material as it was squeezed, the scientists were able to create five new phases of materials, two of which retained their new porous ability at normal pressure.

The scientists couldn't believe what they saw. In order to confirm and reconfirm their findings, they spent the next several years testing and retesting the material. Eventually, they realized that the material was indeed becoming less dense when pressure was applied.

"By applying pressure, we were able to transform a normally dense, nonporous material into a range of new porous materials that can hold twice as much stuff," said Chapman in a news release. "This counterintuitive discovery will likely double the amount of available porous framework materials, which will greatly expand their use in pharmaceutical delivery, sequestration, material separation and catalysis."

The findings are huge boon for researchers and provide a whole new range of materials that could be used for numerous applications. Scientists use these framework materials, which have sponge-like holes in their structure, to trap store and filter materials. The size and shape of their holes make them selectable for certain molecules, which means that they're extremely valuable.

The findings are published in the Journal of the American Chemical Society.