XRD observation of the superionic transition in UH8

Superhydrides constitute a new class of materials with exceptional properties, such as record hydrogen storage, near-ambient temperature superconductivity, and, more recently, hydridic superionicity, all exemplified in the case of LaH10 [1,2]. Ab initio simulations were the first to predict these properties. Unusual hydrogen stoichiometry and high Tc superconductivity have since been experimentally observed. However, superionicity remains to be confirmed, and this was the aim of proposal HC-5662, which focused on studying the thermal expansion of UH7 and UH8 up to their melting points.