Rethinking α−RuCl3: Parameters, models, and phase diagram

$\ensuremath{\alpha}$-RuCl${}_{3}$ promises to harbor an exotic Kitaev spin liquid that could shape the fortunes of the fields of quantum materials and quantum computing. Here, the authors offer a Rosetta Stone for this and other anisotropic-exchange Kitaev materials. The key message is the approach for constraining parameters of their low-energy spin models using experimental observables. This work clears the path to a consistent interpretation of experiments and gives important new insights into the fundamental properties of quantum magnets with spin-orbit coupling.