Octopus
An open-source application for first-principles calculation based on pseudo- potential and real-space basis. It performs electronic-state calculation such as band calculation of solids and structure optimization for a variety of physical systems. The method of time-dependent density functional theory (TDDFT) is implemented, which allows simulation of dynamical phenomena with real-time evolution of electronic states, such as chemical reaction and electronic response to time-dependent external fields. Comes with detailed tutorials and comprehensive manuals.