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The still undiscovered fluid ferroelectric nematic phase is expected to exhibit a much faster and easier response to an external electric field compared to conventional ferroelectric smectic liquid crystals; therefore, the discovery of such a phase could open new avenues in electro‐optic device technology. Here, experimental evidence of a ferroelectric response to a switching electric field in a low molar mass nematic liquid crystal is reported and connected with field‐induced biaxiality. The fluid is made of bent‐core polar molecules and is nematic over a range of 120 °C. Combining repolarization current measurements, electro‐optical characterizations, X‐ray diffraction and computer simulations, ferroelectric switching is demonstrated and it is concluded that the response is due to field‐induced reorganization of polar cybotactic groups within the nematic phase. This work represents significant progress toward the realization of ferroelectric fluids that can be aligned at command with a simple electric field.

An exhaustive structural investigation of a Y-doped ceria (Ce1–x Y x O2–x/2) system over different length scales was performed by combining Rietveld and Pair Distribution Function analyses of X-ray and neutron powder diffraction data. For low doping amounts, which are the most interesting for application, the local structure of Y-doped ceria can be envisaged as a set of distorted CeO2- and Y2O3-like droplets. By considering interatomic distances on a larger scale, the above droplets average out into domains resembling the crystallographic structure of Y2O3. The increasing spread and amount of the domains with doping forces them to interact with each other, leading to the formation of antiphase boundaries. Single phase systems are observed at the average ensemble level.

GENFIT is a new computer code featuring an advanced model-fitting capability to analyse small-angle X-ray and neutron scattering data of macromolecular systems. Batches of experimental curves can be simultaneously best fitted using common parameters issued from combinations of models and, if applicable, constrained by physical and/or phenomenological relations.