| Autor: |
Larsson ED; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55 , DK-5230 Odense M, Denmark., Jørgensen FK; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55 , DK-5230 Odense M, Denmark., Reinholdt P; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55 , DK-5230 Odense M, Denmark., Hedegård ED; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55 , DK-5230 Odense M, Denmark., Kongsted J; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55 , DK-5230 Odense M, Denmark. |
| Abstrakt: |
Core-electron excitations in solvated systems, influenced by solvent geometry and hydrogen bonding, make X-ray absorption spectroscopy (XAS) a valuable tool for assessing solvent-solute interactions. However, calculating XAS spectra with electronic-structure methods has proven challenging due to a delicate interplay between correlation and solvation effects. This study provides a computational procedure for XAS modeling in solvated systems, with water-solvated ammonia and ammonium systems serving as probes. Exploring methodological challenges, we investigate explicit embedding models, specifically the polarizable embedding family, including polarizable density embedding and extended polarizable density embedding. Our linear-response time-dependent density functional theory (LR-TDDFT) XAS calculations reveal the efficiency of this approach, with extended polarizable density embedding emerging as a robust improvement over polarizable density embedding. Contrary to some recent literature, our study challenges the belief that LR-TDDFT cannot accurately describe XAS spectra of ammonia and ammonium solvated in water. |
