| Abstract Scope |
It is a longstanding challenge to unveil the physics of emergent macroscopic behaviors in magnetic materials, including their ultimate extreme at critical points, such as magnetic phase transition, Curie/Neel temperature, negative thermal expansion, Schottky anomaly of heat capacity, and the nature of paramagnetic phase. Here, we show that predicting emergent behaviors can be achieved using the recently proposed zentropy theory, which represents total entropy of a system via a nested formula through the integration of quantum mechanics and statistical mechanics. Using the zentropy theory with temperature-dependent Helmholtz energy for each microstate from first-principles calculations, emergent behaviors can be understood and predicted successfully in magnetic materials, for example, bcc Fe, Invar Fe3Pt, nickelate YNiO3, and Fe-based superconductors of BaFe2As2 and FeSe; indicating the zentropy theory enables more efficient discovery of materials with emergent behaviors in magnetic as well as other materials along with better understanding of their fundamentals. |