Plutonium hexaboride is a correlated topological insulator

We predict that plutonium hexaboride (PuB6) is a strongly correlated topological insulator, with Pu in an intermediate valence state of Pu^2.7+ . Within the combination of dynamical mean field theory and density functional theory, we show that PuB6 is an insulator in the bulk, with non-trivial Z2 topological invariants. Its metallic surface states have large Fermi pocket at X Dirac cones inside the bulk derived electronic states causing a large surface thermal conductivity. PuB6 has also a very high melting temperature therefore it has ideal solid state properties for a nuclear fuel material.