Structural impact on the melting phenomenon of some Cu–Ni alloys through molecular dynamics simulations in condensed-matter physics

This study explores the structural and electronic properties of Cu m Ni n (m[Formula: see text]n [Formula: see text] 4) alloys using an integrated approach that combines molecular dynamics (MD) simulations with density functional theory (DFT), providing a complementary framework beyond conventional single-method studies. Thermodynamic indicators, including total energy, heat capacity, volume variation and Lindemann indices, were employed to characterize atomic vibrational stability and melting behavior. Radial distribution functions and the evolution of face-centered cubic () motifs reveal a pronounced nonlinear structural response to temperature, particularly near the melting transition. The results show that melting temperatures increase nonlinearly with Ni concentration, deviating from simple linear interpolation between pure components, with Ni-rich alloys preserving crystalline order over a wider temperature range. This enhanced thermal stability is attributed to stronger Ni–Ni bonding, consistent with the higher melting temperature of Ni. Structural analysis further confirms that Ni-rich alloys resist disordering more effectively. Complementary DFT calculations reveal that increasing Ni concentration redistributes the electronic states near the Fermi level, indicating composition-dependent electronic and magnetic responses. Overall, the combined MD–DFT analysis highlights the nonlinear coupling between composition, structure and electronic behavior in Cu–Ni alloys.