Simulating ultrafast electron dynamics in molecules using high-order time-dependent density-functional theory schemes

Time-dependent density-functional theory (TDDFT) has emerged as a tool of choice in the simulation and analysis of ultrafast electron dynamics in molecules [1,2]. But the TDDFT equations are nonlinear and obtaining accurate solutions using high-order numerical schemes is challenging. In this presentation I will discuss how high-order symplectic split-operator schemes can be used to simulate ultrafast electron dynamics accurately and efficiently on grids using TDDFT [3]. These symplectic schemes are exactly unitary and time reversible while keeping memory requirements low. I will illustrate the performance of these schemes with far-from equilibrium electronic dynamics in one-dimensional carbon chains.