Near and above ionization electronic excitations with non-hermitian real-time time-dependent density functional theory
We present a real-time time-dependent density functional theory (RT-TDDFT) prescription for capturing near and post-ionization excitations based on non-Hermitian von Neumann density matrix propagation with atom-centered basis sets, tuned range-separated DFT, and a phenomenological imaginary molecular orbital-based absorbing potential to mimic coupling to the continuum. The computed extreme ultraviolet absorption spectra for acetylene (C 2H2), water (H2O), and Freon 12 (CF 2Cl2) agree well with electron energy loss spectroscopy (EELS) data over the range of 0-50 eV. The absorbing potential removes spurious high-energy finite basis artifacts, yielding correct bound-to-bound transitions, metastable (autoionizing) resonance states, and consistent overall absorption shapes. © 2013 American Chemical Society.
Publication Source (Journal or Book title)
Journal of Chemical Theory and Computation
Lopata, K., & Govind, N. (2013). Near and above ionization electronic excitations with non-hermitian real-time time-dependent density functional theory. Journal of Chemical Theory and Computation, 9 (11), 4939-4946. https://doi.org/10.1021/ct400569s