Now researchers have demonstrated a proof of concept for encoding information into artificial molecules, which could enable programmable materials or new types of computers.
The key ingredient is materials called metal-organic frameworks (MOFs). These network-like structures are made up of clusters of metal ions linked with organic ligands, and they're often used as experimental "sponges" for removing pollutants from air and water.
For the new study, researchers at the University of California, Berkeley and Ruhr-Universität Bochum (RUB) set out to make them programmable. Most MOFs are made with one metal at a time, but here the idea is to arrange different metal ions in particular patterns and combinations, to encode information that could potentially be read back by a specially-designed device. It's the same basic principle behind computers reading and writing information in ones and zeroes.