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 MPd₅I₂ structure (M=Ga, In and 3d transition metals). Our study shows that besides the known AlPd₅I₂, the -MPd₅- 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, TiPd₅I₂ and InPd₅I₂ 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. CrPd₅I₂ is a ferromagnet with a large out-of-plane magneto-anisotropy energy, desirable for rare-earth-free permanent magnets.