Look in glass

One of the first lessons in any school science course will tell you that solids have a organised structure, but liquids are amorphous and disorganised, with molecules free to move anywhere within the bulk of the material.

Not so, says James Martin, a chemist at North Carolina State University. Liquids and glasses - also classed as amorphous - have a distinct level of organisation, he says.

What's more, this organisation can be designed and synthesised, leading to new glassy materials with properties that could be useful in optical devices and computers.

Martin formulated his theories while working on the design and synthesis of crystalline materials. He became interested in the liquids and glassy blobs that were often produced along with the crystals. Previous research had shown that when crystals melt, their volume changes very little, indicating that the interactions holding the liquid form together must be very similar to those in the solid.

'If similar bonding interactions hold molecules in liquids, glasses and crystals, it should be possible to engineer the structure of liquids just like it's possible to engineer the structure of crystals,' he explains.

And it does seem to be possible. Martin's research team has experimented with introducing molecules of different substances into glasses and liquids, engineered to 'fit' at an atomic level and to interact with the host substances' molecules. This changes the host substances' properties in a predictable and repeatable way, Martin says in a paper in Nature.

Martin believes this technique could be used to tailor optical, electronic and mechanical properties into glassy substances. 'This new understanding allows us to create the materials that will be the foundation of tomorrow's technology,' he says.