Materials with 5d electrons for future technologies

Materials with 5d electrons show outstanding functional and structural properties. This Perspective systematically analyses the intrinsic electronic structures of materials with 5d electrons to enhance our understanding of their unique functions. Specifically, how the interplay among various factors, including strong nuclear attraction, relativistic effects, strong spin–orbit coupling, large orbital spatial extension, strong crystal field splitting and moderate electron correlation, determines the electronic structures. These electronic characteristics create opportunities for designing new materials and solutions for a variety of applications, including information technologies, quantum sciences, catalysis, aerospace and energy storage. Materials with 5d electrons are receiving increasing attention due to their unique properties and functions. To understand property–function relations, this Perspective analyses six key factors in the electronic structure of 5d electron materials in a range of application areas.