TY  - JOUR
A1  - Vaz da Cruz, Vinícius
A1  - Eckert, Sebastian
A1  - Föhlisch, Alexander
T1  - TD-DFT simulations of K-edge resonant inelastic X-ray scattering within the restricted subspace approximation
T2  - Physical chemistry, chemical physics : PCCP ; a journal of European Chemical Societies
N2  - A scheme for simulations of resonant inelastic X-ray scattering (RIXS) cross-sections within time-dependent density functional theory (TD-DFT) applying the restricted subspace approximation (RSA) is presented. Therein both occupied core and valence Kohn-Sham orbitals are included in the donor-space, while the accepting virtual orbital space in the linear response TD-DFT equations is restricted to efficiently compute both the valence- and core-excited states of the many electron system. This yields a consistent description of all states contributing to the RIXS scattering process within a single calculation. The introduced orbital truncation allows to automatize the method and facilitates RIXS simulations for systems considerably larger than ones accessible with wave-function based methods. Using the nitrogen K-edge RIXS spectra of 2-thiopyridone and its deprotonated anion as a showcase, the method is benchmarked for different exchange-correlation functionals, the impact of the RSA is evaluated, and the effects of explicit solvation are discussed. Improvements compared to simulations in the frozen orbital approximation are also assessed. The general applicability of the framework is further tested by comparison to experimental data from the literature. The use of TD-DFT core-excited states to the calculation of vibrationally resolved RIXS spectra is also investigated by combining potential energy scans along relevant coordinates with wave packet simulations.
Y1  - 2020
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/61445
SN  - 1463-9076
SN  - 1463-9084
VL  - 23
IS  - 3
SP  - 1835
EP  - 1848
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  -