Dynamic evolution of Kohn-Sham electron density in the real-time domain with finite basis expansion

We present a novel method for time-dependent density functional theory calculations on dynamic linear response and electron density evolution in the real-time domain with the finite basis expansion approach of conventional quantum chemistry. To demonstrate the validity and efficiency of this method, dynamic polarizabilities of a water chain and diphenylene molecules are computed by employing the Chebyshev interpolation algorithm, which was developed by Baer and co-workers. The calculated dynamic polarizabilities show good agreement with those obtained from conventional linear response calculations. The density evolution in the real-time domain with application of a long-duration electric field gives electronic conduction in molecules, where a dynamic process of charge transfer is observed with the snapshots of response density in real time. Charge transfer oscillating with the frequency of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) gap is shown in a diphenylene molecule while there is little change in time for a water chain.