AB Initio Study of Surface Energy, Surface Stress and Coupling Coefficient of Au (111)

Shehu, Mustapha (2023-12-10)

Main Thesis


This study investigates ab initio exploration of the Au (111) surface within the generalized gradient approximation, with a primary focus on assessing the convergence properties of this noble metal. An in-depth analysis of the material's response to various computational parameters, including cutoff energy, K-point sampling, and lattice parameter, was conducted to ensure the reliability and consistency of the findings. The theoretical determination of the lattice constant, yielding a value of 4.059 Å, not only aligns quantitatively with experimental measurements but also agrees with calculated values. A noteworthy aspect of this investigation involves reporting on the work function's response to strain, shedding light on how this essential property evolves under external influences. Additionally, the study evaluates the variation of energy per unit cell with varying slab thickness, providing insights into the material's behavior across different structural configurations. The results reveal that Au (111) exhibits a surface energy of 0.5561 𝑒𝑉Å−1, surface stress of 0.18177 𝑒𝑉Å−2and a coupling coefficient of 1.145 eV. These results provides significant implications for understanding the mechanisms associated with electrochemical coupling at an atomic scale, offering crucial insights into the material's behavior across diverse atomic and electronic structures. Thus this work contribute to the understanding of Au (111) surface properties, laying a foundation for advancements in understanding electrochemical phenomena and fostering the development of tailored applications in materials science and nanotechnology.