TY - JOUR
T1 - Evaluation of Aromaticity for Open-Shell Singlet Dicyclopenta-Fused Acenes and Polyacenes Based on a Magnetically Induced Current
AU - Nagami, Takanori
AU - Fujiyoshi, Jun ya
AU - Tonami, Takayoshi
AU - Watanabe, Ken ichiro
AU - Yamane, Masaki
AU - Okada, Kenji
AU - Kishi, Ryohei
AU - Nakano, Masayoshi
AU - Champagne, Benoît
AU - Liégeois, Vincent
N1 - Funding Information:
This work was supported by funds from the bilateral agreement between the JSPS and the F.R.S-FNRS. This work was supported by JSPS KAKENHI Grant Number JP25248007 in Scientific Research (A), Grant Number JP18H01943 in Scientific Research (B), Grant Number JP24109002 in Scientific Research on Innovative Areas “Stimuli-Responsive Chemical Species”, Grant Number JP17H05157 in Scientific Research on Innovative Areas “p-System Figuration”, Grant Number JP26107004 in Scientific Research on Innovative Areas “Photosynergetics”, and Grant Number JP26107525 in Scientific Research on Innovative Areas “Sciences of Atomic Layers”. V.L. thanks the F.R.S.-FNRS for his Research Associate position. M.N. also thanks the financial support by King Khalid University through the Grant RCAMS/KKU/ 001-16 under the Research Center for Advanced Materials Science at King Khalid University, Kingdom of Saudi Arabia. T.N. thanks to the JSPS Research Fellowship for Young Scientists (No. JP18J20887). Theoretical calculations are partly performed using the Research Center for Computational Science, Okazaki, Japan. Part of the calculations were performed on the computers of the Consortium des Équipements de Calcul Intensif (CÉCI) and mostly those of the Technological Platform of High-Performance Computing, for which we gratefully acknowledge the financial support of the FNRS-FRFC (Conventions No. 2.4.617.07.F and 2.5020.11) and of the University of Namur.
Funding Information:
This work was supported by funds from the bilateral agreement between the JSPS and the F.R.S-FNRS. This work was supported by JSPS KAKENHI Grant Number JP25248007 in Scientific Research (A), Grant Number JP18H01943 in Scientific Research (B), Grant Number JP24109002 in Scientific Research on Innovative Areas “Stimuli-Responsive Chemical Species”, Grant Number JP17H05157 in Scientific Research on Innovative Areas “π-System Figuration”, Grant Number JP26107004 in Scientific Research on Innovative Areas “Photosynergetics”, and Grant Number JP26107525 in Scientific Research on Innovative Areas “Sciences of Atomic Layers”. V.L. thanks the F.R.S.-FNRS for his Research Associate position. M.N. also thanks the financial support by King Khalid University through the Grant RCAMS/KKU/001-16 under the Research Center for Advanced Materials Science at King Khalid University, Kingdom of Saudi Arabia. T.N. thanks to the JSPS Research Fellowship for Young Scientists (No. JP18J20887). Theoretical calculations are partly performed using the Research Center for Computational Science, Okazaki, Japan. Part of the calculations were performed on the computers of the Consortium des Équipements de Calcul Intensif (CÉCI) and mostly those of the Technological Platform of High-Performance Computing, for which we gratefully acknowledge the financial support of the FNRS- FRFC (Conventions No. 2.4.617.07.F and 2.5020.11) and of the University of Namur.
Publisher Copyright:
© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/9/12
Y1 - 2018/9/12
N2 - The aromaticity of dicyclopenta-fused acenes (DPAs) and polyacenes (PAs) of increasing size has been studied by evaluation with the GIMIC method at the DFT level of the magnetically-induced currents (MICs), and by analyzing their spatial distributions. For these open-shell singlet molecules, spin-restricted and -unrestricted treatments provide very different MICs, the latter ones providing the most reliable solution. These MICs and the differences between spin-restricted and -unrestricted treatments are interpreted in terms of the bond current strengths and the current gradients, which indicate the bond aromaticity and enable the spatial distributions of the diatropic and paratropic currents to be analyzed, respectively. In particular, they allow the rationalization of the MICs in correlation with the odd-electron density distributions and their diradical characters. These calculations demonstrate that 1) in increasingly large PAs the bond current strengths get smaller and smaller than in benzene and get almost similar in the central and terminal rings, 2) for DPAs the MICs increase from dominant paratropic currents and antiaromaticity in the small compounds to diatropic currents and aromaticity in the larger ones, and 3) in the largest DPAs, the central rings are characterized by large diatropic currents and the terminal five-membered rings, for which the odd-electron densities are localized by weak ones.
AB - The aromaticity of dicyclopenta-fused acenes (DPAs) and polyacenes (PAs) of increasing size has been studied by evaluation with the GIMIC method at the DFT level of the magnetically-induced currents (MICs), and by analyzing their spatial distributions. For these open-shell singlet molecules, spin-restricted and -unrestricted treatments provide very different MICs, the latter ones providing the most reliable solution. These MICs and the differences between spin-restricted and -unrestricted treatments are interpreted in terms of the bond current strengths and the current gradients, which indicate the bond aromaticity and enable the spatial distributions of the diatropic and paratropic currents to be analyzed, respectively. In particular, they allow the rationalization of the MICs in correlation with the odd-electron density distributions and their diradical characters. These calculations demonstrate that 1) in increasingly large PAs the bond current strengths get smaller and smaller than in benzene and get almost similar in the central and terminal rings, 2) for DPAs the MICs increase from dominant paratropic currents and antiaromaticity in the small compounds to diatropic currents and aromaticity in the larger ones, and 3) in the largest DPAs, the central rings are characterized by large diatropic currents and the terminal five-membered rings, for which the odd-electron densities are localized by weak ones.
KW - aromaticity
KW - GIMIC
KW - odd-electron density
KW - open-shell systems
KW - spin-unrestricted method
UR - http://www.scopus.com/inward/record.url?scp=85053228999&partnerID=8YFLogxK
U2 - 10.1002/chem.201802696
DO - 10.1002/chem.201802696
M3 - Article
AN - SCOPUS:85053228999
SN - 0947-6539
VL - 24
SP - 13457
EP - 13466
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 51
ER -