Application of Density Functional Theory for the Calculation of the Non‐Linear Optical Properties of Materials: A Comprehensive Review

The development of photonic and optoelectronic technologies, such as laser systems, high‐speed optical communication, quantum information science, and medical imaging, relies significantly on nonlinear optical (NLO) materials. Understanding and predicting their nonlinear optical responses is paramount for material innovation. Density Functional Theory (DFT) is important computational method for predicting electronic structure and calculating optical material properties. The present review gives an overview of application of DFT to study NLO materials that can be classified into organic molecules, inorganic crystals, metal‐organic frameworks (MOFs), hybrid perovskites, and 2D materials. We have also discussed the challenges, recent advancements, and emerging research areas in this field.