Cost-Efficient High-Resolution Linear Absorption Spectra Through Extrapolating the Dipole Moment from Real-Time Time-Dependent Electronic-Structure Theory

• DOI: 10.48550/arxiv.2307.01511
• Publication Date: 2023-01-01
• Authors: Eirill Hauge; Håkon Emil Kristi...; Lukas Konecny; Marius Kadek; Michal Repiský; Thomas Bondo Pede...
• Keywords: Chemical Physics (physics.chem-ph); Physics - Chemical Physics; FOS: Physical sciences; 540; 530

We present a novel function fitting method for approximating the propagation of time-dependent electric dipole moment from real-time electronic structure calculations. Real-time calculations absorption spectrum require discrete Fourier transforms moment. The spectral resolution is determined by total time, i.e. trajectory length moment, causing high computational cost. Our developed uses on shorter trajectories achieving arbitrary through extrapolation. Numerical testing shows that can reproduce high-resolution spectra using short trajectories. converges with as little 100 a.u. some systems, though difficulty converging increases density. also introduce an error estimate fit, reliably assessing its convergence and hence quality approximated spectrum.