Modified embedded-atom method potential for cadmium

Abstract

The second nearest-neighbor modified embedded atom method (2NN MEAM) is a semi-empirical simulation technique designed to calculate materials properties of metallic and covalent solids. It is a strong candidate for calculation of site occupation, defect association, and diffusion mechanisms in intermetallic compounds, which would provide a tool for interpreting experimental results and for predicting new, interesting measurements to perform. Potentials for 39 elements can be found in the literature, but cadmium, an important element for perturbed angular correlation spectroscopy (PAC), is absent. The purpose of this work was to develop a 2NN-MEAM potential for cadmium. Empirical parameters were determined through optimization of the potential’s ability to reproduce known physical properties of pure cadmium including cohesive energy, lattice parameters, elastic constants, structural enthalpy differences, surface enthalpy, vacancy formation energy, thermal expansion, and specific heat. Prospects for using this new potential with 2NN MEAM potentials for other elements to help interpret previous PAC studies of cadmium diffusion in intermetallic compounds will be discussed.