An efficient method to generate amorphous structures based on local geometry

We propose an efficient method that generates amorphous structures based on information on the shortrange order such as bond lengths and coordination numbers. The base amorphous structure is constructed in the ‘‘seed-and-coordinate’’ style, which conforms to the given short-range order. The structure is further annealed to relax the atomic bonding and establish the medium-range order. The computational cost of the proposed method is less than 10% of the standard melt-quench approach. We combine this method with ab initio calculations and generate amorphous structures for various materials such as a-Si, a-SiO2, a-Ge2Sb2Te5, and a-InGaZnO4. The obtained structures are close to those from melt-quench simulations in terms of atomic and electronic structures. To substantiate the computational efficiency, we generate a-GeSe with 512 atoms in the unit cell. The large cell allows us for identifying the mobility edge