title: Modified Z method to calculate melting curve by molecular dynamics.
abstract: We extend the recently proposed Z method of estimating the melting temperature from a complete liquid and propose a modified Z method to calculate the melting temperature from a solid-liquid coexistence state. With the simulation box of rectangular parallelepiped, an initial structure of perfect lattice can run in the microcanonical ensemble to achieve steady solid-liquid coexistence state. The melting pressure and temperature are estimated from the coexistence state. For the small system with 1280 atoms, the simulation results show that the melting curve of copper has a good agreement with the experiments and is identical in accuracy with the results of the two-phase coexistence method with 24 000 atoms in the literature. Moreover, the method is conceptually simpler than the two-phase coexistence method.
authors.affiliation: Data Center for High Energy Density Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094, China.
authors.forename: Shuaichuang
authors.initials: S
authors.lastname: Wang
authors.forename: Gongmu
authors.initials: G
authors.lastname: Zhang
authors.forename: Haifeng
authors.initials: H
authors.lastname: Liu
authors.forename: Haifeng
authors.initials: H
authors.lastname: Song