First-principles calculations predict a new tetragonal layered van der Waals compound MPd5I2 with interesting topological and magnetic properties in both bulk and 2D single layer.
Layered materials with weak van der Waals bonding can be exfoliated to a few atomic layers. Such few-layer and Moiré geometries can serve as tunable platforms for the discovery of quantum and topological states in tetragonal systems.
- Convex hull is calculated from density-functional theory (DFT) for MPd5I2 (M=Ga, In and 3d transition metals) to predict thermodynamic stability to compare with known AlPd5I2.
- Band structure calculations reveal TiPd5I2 is a Dirac semimetal also hosting topological surface states with its 2D single layer being a quantum spin Hall insulator. InPd5I2 has similar features.
- Ferromagnetic CrPd5I2 has a large magnetic anisotropy with out-of-plane easy axis, providing a promising candidate for rare-earth-free permanent magnets and Weyl nodal loops.
N. K. Nepal, T. J. Slade, J.M. Blawat, A. Eaton, J. C. Palmstrom, B. G. Ueland, A. Kaminski, R. J. McQueeney, R. D. McDonald, P. C. Canfield, & L.-L. Wang (2025). Design and predict tetragonal van der Waals layered quantum materials of MPd5I2 (M=Ga, In and 3d transition metals). npj 2D Materials and Applications 9(15). http://doi.org/10.1038/s41699-025-00536-6