Excited states and excitonic interactions in prototypic polycyclic aromatic hydrocarbon dimers as models for graphitic interactions in carbon dots

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388963%3A_____%2F19%3A00507445" target="_blank" >RIV/61388963:_____/19:00507445 - isvavai.cz</a>

Result on the web

<a href="https://pubs.rsc.org/en/content/articlelanding/2019/CP/C9CP00635D#!divAbstract" target="_blank" >https://pubs.rsc.org/en/content/articlelanding/2019/CP/C9CP00635D#!divAbstract</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c9cp00635d" target="_blank" >10.1039/c9cp00635d</a>

Result language

angličtina

Original language name

Excited states and excitonic interactions in prototypic polycyclic aromatic hydrocarbon dimers as models for graphitic interactions in carbon dots

Original language description

The study of electronically excited states of stacked polycyclic aromatic hydrocarbons (PAHs) is of great interest due to promising applications of these compounds as luminescent carbon nanomaterials such as graphene quantum dots (GQDs) and carbon dots (CDs). In this study, the excited states and excitonic interactions are described in detail based on four CD model dimer systems of pyrene, coronene, circum-1-pyrene and circum-1-coronene. Two multi-reference methods, DFT/MRCI and SC-NEVPT2, and two single-reference methods, ADC(2) and CAM-B3LYP, have been used for excited state calculations. The DFT/MRCI method has been used as a benchmark method to evaluate the performance of the other ones. All methods produce useful lists of excited states. However, an overestimation of excitation energies and an inverted ordering of states, especially concerning the bright HOMO-LUMO excitation, are observed. In the pyrene-based systems, the first bright state appears among the first four states, whereas the number of dark states is significantly larger for the coronene-based systems. Fluorescence emission properties are addressed by means of geometry optimization in the S-1 state. The inter sheet distances for the S-1 state decrease in comparison to the corresponding ground-state values. These reductions are largest for the pyrene dimer and decrease significantly for the larger dimers. Several minima have been determined on the S-1 energy surface for most of the dimers. The largest variability in emission energies is found for the pyrene dimer, whereas in the other cases a more regular behavior of the emission spectra is observed.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10403 - Physical chemistry

Project

<a href="/en/project/GA16-16959S" target="_blank" >GA16-16959S: Theoretical Description of the Excited states of Covalently and Non-covalently Functionalized Graphenes</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Physical Chemistry Chemical Physics

ISSN

1463-9076

e-ISSN

—

Volume of the periodical

21

Issue of the periodical within the volume

18

Country of publishing house

GB - UNITED KINGDOM

Number of pages

12

Pages from-to

9077-9088

UT code for WoS article

000472922500009

EID of the result in the Scopus database

2-s2.0-85065607269