Design and Predict Tetragonal van der Waals Layered Quantum Materials of MPd5I2 (M=Ga, In and 3d Transition Metals)

Quantum materials with stacking van der Waals (vdW) layers that can host non-trivial band structure topology and magnetism have shown many interesting properties. Here using high-throughput density functional theory calculations, we design and predict tetragonal vdW-layered quantum materials in the MPd ₅ I ₂ structure (M = Ga, In and 3 d transition metals). Our study shows that besides the known AlPd ₅ I ₂ , the -MPd ₅ - structural motif of three-layer slabs separated by two I layers can host a variety of metal elements giving arise to topological interesting features and highly tunable magnetic properties in both bulk and single layer 2D structures. Among them, TiPd ₅ I ₂ and InPd ₅ I ₂ host a pair of Dirac points and a likely strong topological insulator state for the band manifolds just above and below the top valence band, respectively, with their single layers possibly hosting quantum spin Hall states. CrPd ₅ I ₂ is a ferromagnet with a large out-of-plane magneto-anisotropy energy, desirable for rare-earth-free permanent magnets.