The outline of the present paper is as follows: First, a brief theoretical explanation of relativistic CASPT2/RASPT2 is provided. Second, the entire program workflow is visualized, and a graphical user interface (GUI) program for generating CASPT2/RASPT2 input is introduced, along with demonstrations of parallelization efficiencies on CASCI/CASPT2. Finally, as part of benchmark calculations, the vertical excitation energies of the gas-phase uranyl (UO2 2+ ) molecule were obtained at the RASPT2 level and listed along with previously reported data obtained using different electron correlation methods and relativistic Hamiltonians.