The presence of adsorbates on a metal surface can significantly affect the surface properties of the metal. Density Functional Theory DFT calculations can be used to study these effects and provide insights into the interactions between adsorbates and metal surfaces. Here are some ways in which adsorbates can affect the surface properties of a metal:1. Electronic structure: Adsorbates can modify the electronic structure of the metal surface by donating or accepting electrons. This can lead to changes in the density of states near the Fermi level, which in turn can affect the reactivity and catalytic properties of the surface. DFT calculations can be used to analyze the electronic structure of the adsorbate-metal system and identify the changes in the density of states.2. Geometric structure: The adsorption of molecules on a metal surface can cause a rearrangement of the surface atoms, leading to changes in the surface geometry. DFT calculations can be used to determine the most stable adsorption sites and geometries for the adsorbate-metal system, as well as to calculate the adsorption energy, which is a measure of the strength of the interaction between the adsorbate and the surface.3. Reactivity: The presence of adsorbates can affect the reactivity of the metal surface by modifying the activation energy barriers for various surface reactions. DFT calculations can be used to study the reaction pathways and calculate the activation energy barriers for different reaction steps, providing insights into the effect of adsorbates on the catalytic properties of the metal surface.4. Vibrational properties: Adsorbates can also affect the vibrational properties of the metal surface, which can be important for understanding the dynamics of surface reactions. DFT calculations can be used to calculate the vibrational frequencies and modes of the adsorbate-metal system, providing information about the vibrational coupling between the adsorbate and the surface.In summary, Density Functional Theory calculations can be a powerful tool for studying the effects of adsorbates on the surface properties of a metal. By providing detailed information about the electronic, geometric, and vibrational properties of the adsorbate-metal system, DFT calculations can help to understand the underlying mechanisms of adsorption and surface reactions, and guide the design of more efficient catalysts and materials.