Charge transfer excitations in TDDFT : A ghost-hunter index

© 2017 Wiley Periodicals, Inc.

Bibliographische Detailangaben
Veröffentlicht in:Journal of computational chemistry. - 1984. - 38(2017), 25 vom: 30. Sept., Seite 2151-2156
1. Verfasser: Campetella, Marco (VerfasserIn)
Weitere Verfasser: Maschietto, Federica, Frisch, Mike J, Scalmani, Giovanni, Ciofini, Ilaria, Adamo, Carlo
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2017
Zugriff auf das übergeordnete Werk:Journal of computational chemistry
Schlagworte:Journal Article Research Support, Non-U.S. Gov't TD-DFT charge transfer excitations density-functional theory ghost states molecular descriptors
Beschreibung
Zusammenfassung:© 2017 Wiley Periodicals, Inc.
This work presents a new index, MAC , enabling the on-the-fly detection of ghost charge transfer (CT) states, a major problem in time-dependent density-functional theory calculations. This computationally inexpensive index, derived as a modification of the Mulliken estimation of transition energy for CT excitations, relies on two basic ingredients: an effective CT distance, computed using our density-based index (DCT ), and an orbital weighted estimation of the Ionization Potential and Electron Affinity. Some model systems, representative of both intermolecular and intramolecular CT excitations, were chosen as test cases. The robustness of our approach was verified by analyzing the behavior of functionals belonging to different classes (GGA, global hybrids and range separated hybrids). The results obtained show that ghost states are correctly spotted, also in the delicate case of intramolecular excitations displaying substantial donor-bridge-acceptor delocalization, in a regime for which the standard Mulliken formulation attends its limits. © 2017 Wiley Periodicals, Inc
Beschreibung:Date Revised 20.11.2019
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1096-987X
DOI:10.1002/jcc.24862