Molecular memory near room temperature in an iron polyanionic complex

Summary Bistable molecules represent a potential miniaturization limit for high-density information technologies. However, exhibit memory effect typically at very low temperatures. This is the case of spin-crossover (SCO) complexes, where concept molecular has not been considered due to fast spin-state interconversion all previous systems. Breaking this principle, here we report slow relaxation process found in an SCO iron-triazole polyanionic complex. Multiple experimental evidences confirm opening thermal hysteresis upon solid dilution and even liquid solution. Density functional theory (DFT) calculations reveal origin unexpected phenomenon appearance energy barrier that slows down processes level. These results show how may store room temperature, unique opportunities data storage.