The Lack of Resonance Problem in Coherent Control with Real-Time Time-Dependent Density Functional Theory

We will show that adiabatic real-time TDDFT predicts a time- and energy-dependent electronic structure of molecules, which makes it hard to combine TDDFT with coherent control schemes that depend on resonance conditions. In this study, we use sequences of ultrashort pulses, separated by long intervals of field free evolution, to illustrate this phenomenon for two molecules and two functionals. In coherent control scenarios, long laser pulses, with many oscillation periods, excite the system continuously and, in this way produce, a time-dependent electronic structure.