The electronic structure of a material plays a crucial role in determining its electrical conductivity. Electrical conductivity is the ability of a material to conduct electric current, and it depends on the availability and mobility of charge carriers electrons or holes within the material. The electronic structure, which includes the arrangement of electrons in energy levels or bands, determines the availability of these charge carriers.In a material, the electronic structure can be described by the arrangement of electrons in valence and conduction bands. The valence band is the highest energy band that is completely filled with electrons, while the conduction band is the next higher energy band that is partially filled or empty. The energy gap between these two bands is called the bandgap.In conductors, the valence and conduction bands overlap, allowing electrons to move freely between them and conduct electric current. In semiconductors, there is a small bandgap between the valence and conduction bands, which can be overcome by thermal energy or other external factors, enabling the material to conduct electricity. In insulators, the bandgap is large, making it difficult for electrons to move from the valence to the conduction band, resulting in low electrical conductivity.Density functional theory DFT is a computational method used to study the electronic structure of materials. It is based on the idea that the ground state properties of a system can be determined by the electron density rather than the many-body wavefunction. DFT calculations can provide valuable insights into the electronic structure of a material, including the band structure, density of states, and the bandgap.DFT has been successfully used to predict the electrical conductivity of various materials by calculating their electronic structure. However, it is important to note that DFT has some limitations, such as the choice of exchange-correlation functional, which can affect the accuracy of the predictions. Additionally, DFT is a ground state theory and does not account for temperature effects or electron-phonon interactions, which can also influence the electrical conductivity.In summary, the electronic structure of a material is a key factor in determining its electrical conductivity. Density functional theory calculations can provide valuable insights into the electronic structure and help predict the electrical conductivity of materials, but it is essential to consider the limitations and assumptions of the method.