High-Pressure Characterization of the La-H system

Hydrogen-containing materials are at the forefront of research into high-temperature superconductivity. Despite holding the record high superconducting critical temperature (Tc) in LaH10 of 250K at an applied pressure of 170 GPa, the lanthanum-hydrogen system remains poorly characterized at pressures below 100 GPa. Our own preliminary work shows both previously unknown hydrogen compounds within this pressure range and extensive stoichiometric changes that were unknown within the lanthanum hydrogen system. XRD data allows these changes in hydrogen content and for the distortion and decomposition processes of known superconducting hydrides to be tracked. Such knowledge is vital to stabilise these high-Tc structures at lower pressures.