Construction of Tight-Binding Models for Monolayer Biphenylene Network from Ab Initio Wannier Functions

초록

Developing a computationally efficient yet accurate theoretical model is crucial for studying complex materials. In this work, we construct such a tight-binding (TB) model for a newly synthesized carbon monolayer, biphenylene network (BPN). Our TB models start with the full Hamiltonian obtained from density functional theory (DFT) calculations and maximally localized Wannier functions, ensuring they are physically well-grounded. We apply two methods to build TB models from the Wannier-based DFT Hamiltonian. First, we create a simplified TB model by truncating the long-range hopping parameters beyond a certain distance cutoff. We determine the distance cutoff at which the truncated model sufficiently matches the DFT band structures. As a more efficient alternative, we employ a weighted parameter optimization to refine TB models built with smaller cutoffs. By specifically targeting the bands that constitute the Fermi surfaces, this approach corrects inaccuracies in their description and yields a highly efficient model that reproduces all key electronic features with a significantly reduced number of parameters. The optimized TB model for BPN serves as a powerful tool for future large-scale simulations of the material's properties. Furthermore, the two-step workflow presented here, truncation followed by weighted optimization, provides a general and effective strategy for constructing TB models for other materials with complex electronic structures.