Ab initio phase diagram and nucleation of gallium.

ABSTRACT: Elemental gallium possesses several intriguing properties, such as a low melting point, a density anomaly and an electronic structure in which covalent and metallic features coexist. In order to simulate this complex system, we construct an ab initio quality interaction potential by training a neural network on a set of density functional theory calculations performed on configurations generated in multithermal-multibaric simulations. Here we show that the relative equilibrium between liquid gallium, ?-Ga, ?-Ga, and Ga-II is well described. The resulting phase diagram is in agreement with the experimental findings. The local structure of liquid gallium and its nucleation into ?-Ga and ?-Ga are studied. We find that the formation of metastable ?-Ga is kinetically favored over the thermodinamically stable ?-Ga. Finally, we provide insight into the experimental observations of extreme undercooling of liquid Ga.

SUBMITTER: Niu H 

PROVIDER: S-EPMC7253470 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature