Ítem


Analysis of a Compound with Triplet States Stabilized by Potentially Baird-Aromatic [10] Annulenyl Dicationic Rings

The low-lying triplet state of a recently published compound (TMTQ, Angew. Chem. Int. Ed. 2015, 20, 5888), was analyzed quantum chemically in light of suggestions that it is influenced by Baird-aromaticity. Two mesomeric structures describe this state; a zwitterionic Baird-aromatic structure with a triplet biradical 8pi-electron methano[10]annulene (M10A) dicationic ring, and a Hückel-aromatic with a neutral closed-shell 10pi-electron ring. According to charge and spin density distributions, the Hückel-aromatic structure dominates the triplet state (the Baird-aromatic contributes at most 12%), and separation of the FLU aromaticity index into alpha and beta electron contributions emphasizes this finding. The small singlet-triplet energy gap is due to Hückel-aromaticity of the M10A ring, clarified by comparison to the smaller analogues of TMTQ. Yet, TMTQ and its analogues are Hückel-Baird hybrids allowing for tuning between closed-shell 4n+2 Hückel-aromaticity and open-shell 4n Baird-aromaticity

This work has been supported by the Swedish Research Council (project grant 621-2011-4177), Ministerio de Economía y Competitividad (MINECO) of Spain (Project CTQ2014-54306-P) and the Generalitat de Catalunya (project 2014SGR931, Xarxa de Referència en Química Teòrica i Computacional, and ICREA Academia 2014 prize for M.S.). F.F. acknowledges financial support of the Beatriu de Pinós programme from AGAUR for the postdoctoral grants BP_A_00339 and BP_A2_00022. M.S. and F.F. are grateful to the European Union (EU) for FEDER fund number UNGI10-4E-801

© Chemistry-A European Journal, 2016, vol. 22, núm. 8, p. 2793-2800

Wiley-VCH Verlag

Autor: Jorner, Kjell
Feixas Geronès, Ferran
Ayub, Rabia
Lindh, Roland
Solà i Puig, Miquel
Ottosson, Henrik
Data: 2016
Resum: The low-lying triplet state of a recently published compound (TMTQ, Angew. Chem. Int. Ed. 2015, 20, 5888), was analyzed quantum chemically in light of suggestions that it is influenced by Baird-aromaticity. Two mesomeric structures describe this state; a zwitterionic Baird-aromatic structure with a triplet biradical 8pi-electron methano[10]annulene (M10A) dicationic ring, and a Hückel-aromatic with a neutral closed-shell 10pi-electron ring. According to charge and spin density distributions, the Hückel-aromatic structure dominates the triplet state (the Baird-aromatic contributes at most 12%), and separation of the FLU aromaticity index into alpha and beta electron contributions emphasizes this finding. The small singlet-triplet energy gap is due to Hückel-aromaticity of the M10A ring, clarified by comparison to the smaller analogues of TMTQ. Yet, TMTQ and its analogues are Hückel-Baird hybrids allowing for tuning between closed-shell 4n+2 Hückel-aromaticity and open-shell 4n Baird-aromaticity
This work has been supported by the Swedish Research Council (project grant 621-2011-4177), Ministerio de Economía y Competitividad (MINECO) of Spain (Project CTQ2014-54306-P) and the Generalitat de Catalunya (project 2014SGR931, Xarxa de Referència en Química Teòrica i Computacional, and ICREA Academia 2014 prize for M.S.). F.F. acknowledges financial support of the Beatriu de Pinós programme from AGAUR for the postdoctoral grants BP_A_00339 and BP_A2_00022. M.S. and F.F. are grateful to the European Union (EU) for FEDER fund number UNGI10-4E-801
Format: application/pdf
ISSN: 0947-6539 (versió paper)
1521-3765 (versió electrònica)
Accés al document: http://hdl.handle.net/10256/12193
Llenguatge: eng
Editor: Wiley-VCH Verlag
Col·lecció: MINECO/PE 2015-2017/CTQ2014-54306-P
AGAUR/2014-2016/2014 SGR-931
Versió postprint del document publicat a: http://dx.doi.org/10.1002/chem.201504924
Articles publicats (D-Q)
És part de: © Chemistry-A European Journal, 2016, vol. 22, núm. 8, p. 2793-2800
Drets: Tots els drets reservats
Matèria: Aromaticitat (Química)
Aromaticity (Chemistry)
Títol: Analysis of a Compound with Triplet States Stabilized by Potentially Baird-Aromatic [10] Annulenyl Dicationic Rings
Tipus: info:eu-repo/semantics/article
Repositori: DUGiDocs

Matèries

Autors