In conclusion, the LanL2DZ basis set has proven to be a valuable tool in DFT simulations for studying cisplatin encapsulation within metallacages. Its development as an Effective Core Potential (ECP) basis set allows for efficient modelling of transition metals while addressing relativistic effects in deep core electrons . Despite its limitations, such as the absence of polarization and diffuse functions, LanL2DZ offers a practical balance between computational efficiency and accuracy. This capability makes it particularly well-suited for exploring the encapsulation process of cisplatin, providing crucial insights into the stability and interactions within metallacage systems.