Lattice built with negative thermal expansion properties reveals unique relaxation mechanism

https://phys.org/news/2023-05-lattice-built-negative-thermal-expansion.html

"tiny, cage-like structures that shrink a certain amount when exposed to a certain temperature. The shrinking occurs due to spring-like properties of the cages. They were made by introducing organic linkers into a skeleton made of a metal-organic rotaxane. U3(bcbpy)3(CB8)... negative thermal expansion that corresponded with a given recovery stage in the material. The researchers suggest the material could have applications where size and shape control in response to heat are needed"

Related: Researchers engineer a material that can perform different tasks depending on temperature

https://techxplore.com/news/2023-11-material-tasks-temperature.html