Tuning the UV spectrum of PAHs by means of different N-doping types taking pyrene as paradigmatic example: categorizationviavalence bond theory and high-level computational approaches

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388963%3A_____%2F20%3A00533461" target="_blank" >RIV/61388963:_____/20:00533461 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61989592:15310/20:73604176

Výsledek na webu

<a href="https://doi.org/10.1039/D0CP02688C" target="_blank" >https://doi.org/10.1039/D0CP02688C</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d0cp02688c" target="_blank" >10.1039/d0cp02688c</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Tuning the UV spectrum of PAHs by means of different N-doping types taking pyrene as paradigmatic example: categorizationviavalence bond theory and high-level computational approaches

Popis výsledku v původním jazyce

Tuning of the electronic spectra of carbon dots by means of inserting heteroatoms into the pi-conjugated polycyclic aromatic hydrocarbon (PAH) system is a popular tool to achieve a broad range of absorption and emission frequencies. Especially nitrogen atoms have been used successfully for that purpose. Despite the significant progress achieved with these procedures, the prediction of specific shifts in the UV-vis spectra and the understanding of the electronic transitions is still a challenging task. In this work, high-level quantum chemical methods based on multireference (MR) and single-reference (SR) methods have been used to predict the effect of different nitrogen doping patterns inserted into the prototypical PAH pyrene on its absorption spectrum. Furthermore, a simple classification scheme based on valence bond (VB) theory and the Clar sextet rule in combination with the harmonic oscillator measure of aromaticity (HOMA) index was applied to arrange the different doping structures into groups and rationalize their electronic properties. The results show a wide variety of mostly redshifts in the spectra as compared to the pristine pyrene case. The most interesting doping structures with the largest red shifts leading to absorption energies below one eV could be readily explained by the occurrence of diradical VB structures in combination with Clar sextets. Moreover, analysis of the electronic transitions computed with MR methods showed that several of the low-lying excited states possess double-excitation character, which cannot be realized by the popular SR methods and, thus, are simply absent in the calculated spectra.

Název v anglickém jazyce

Tuning the UV spectrum of PAHs by means of different N-doping types taking pyrene as paradigmatic example: categorizationviavalence bond theory and high-level computational approaches

Popis výsledku anglicky

Tuning of the electronic spectra of carbon dots by means of inserting heteroatoms into the pi-conjugated polycyclic aromatic hydrocarbon (PAH) system is a popular tool to achieve a broad range of absorption and emission frequencies. Especially nitrogen atoms have been used successfully for that purpose. Despite the significant progress achieved with these procedures, the prediction of specific shifts in the UV-vis spectra and the understanding of the electronic transitions is still a challenging task. In this work, high-level quantum chemical methods based on multireference (MR) and single-reference (SR) methods have been used to predict the effect of different nitrogen doping patterns inserted into the prototypical PAH pyrene on its absorption spectrum. Furthermore, a simple classification scheme based on valence bond (VB) theory and the Clar sextet rule in combination with the harmonic oscillator measure of aromaticity (HOMA) index was applied to arrange the different doping structures into groups and rationalize their electronic properties. The results show a wide variety of mostly redshifts in the spectra as compared to the pristine pyrene case. The most interesting doping structures with the largest red shifts leading to absorption energies below one eV could be readily explained by the occurrence of diradical VB structures in combination with Clar sextets. Moreover, analysis of the electronic transitions computed with MR methods showed that several of the low-lying excited states possess double-excitation character, which cannot be realized by the popular SR methods and, thus, are simply absent in the calculated spectra.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Physical Chemistry Chemical Physics

ISSN

1463-9076

e-ISSN

—

Svazek periodika

22

Číslo periodika v rámci svazku

38

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

13

Strana od-do

22003-22015

Kód UT WoS článku

000576194400039

EID výsledku v databázi Scopus

2-s2.0-85092681336