Conflicting evidence for ferroelectricity

Organic ferroelectric materials operating at room temperature are in demand in the emerging field of lightweight, flexible and environ- mentally friendly electronics. Tayi et al.1 reported room-temperature ferroelectricity in organic mixed-stack charge-transfer crystals, produced using a supramolecular design concept—the lock-arm supramolecular ordering (LASO)—that synergistically combines inter- molecular charge transfer and hydrogen bonds2,3. Here we present an independent experimental investigation that found no evidence for ferroelectricity in one of the LASO compounds described in ref. 1 and, together with theoretical calculations, demonstrates that a possible ferroelectric behaviour is not of electronic origin as proposed in ref. 1. We therefore question the reproducibility of1the room- temperature ferroelectricity claimed for LASO systems.