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arXiv · 1412.0996

An efficient algorithm for time propagation within time-dependent density functional theory

J. K. Dewhurst·K. Krieger·S. Sharma·E. K. U. Gross
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Abstract

An efficient algorithm for time propagation of the time-dependent Kohn-Sham equations is presented. The algorithm is based on dividing the Hamiltonian into small time steps and assuming that it is constant over these steps. This allows for the time-propagating Kohn-Sham wave function to be expanded in the instantaneous eigenstates of the Hamiltonian. The stability and efficiency of the algorithm are tested not just for non-magnetic but also for fully non-collinear magnetic systems. We show that even for delicate properties, like magnetization density, large time-step sizes can be used indicating the stability and efficiency of the algorithm.

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J. K. Dewhurst, K. Krieger, S. Sharma, E. K. U. Gross. 2014-12-02. An efficient algorithm for time propagation within time-dependent density functional theory. https://arxiv.org/abs/1412.0996

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