Journal
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
Volume 12, Issue 6, Pages 2652-2660Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jctc.6b00245
Keywords
-
Funding
- European Research Council (ERC) [306528]
- Swiss National Science Foundation [156001]
- ERC
- Region des Pays de la Loire [Marches-278845]
- LUMOMAT project
- Basque Government [IT588-13]
- CONACyT [571900]
Ask authors/readers for more resources
The description of low-lying pi pi* states of linear acenes by standard electronic structure methods is known to be challenging. Here, we broaden the framework of this problem by considering a set of fused heteroaromatic rings and demonstrate that standard electronic structure methods do not provide a balanced description of the two (typically) lowest singlet state (L-a and L-b) excitations. While the L-b state is highly sensitive to correlation effects, L-a suffers from the same drawbacks as charge transfer excitations. We show that the comparison between CIS/CIS(D) can serve as a diagnostic for detecting the two problematic excited states. Standard TD-DFT and even its spin-flip variant lead to inaccurate excitation energies and interstate gaps, with only a double hybrid functional performing somewhat better. The complication inherent to a balanced description of these states is so important that even CC2 and ADC(2) do not necessarily match the ADC(3) reference.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available