Acenes and phenacenes in their lowest-lying triplet states. Does kinked remain more stable than straight?
dc.contributor.author
dc.date.accessioned
2021-07-30T09:42:21Z
dc.date.available
2022-10-28T05:46:32Z
dc.date.issued
2021-07-05
dc.identifier.issn
1463-9076
dc.identifier.uri
dc.description.abstract
The larger stability of phenacenes compared to their acene isomers in their ground states is attributed to the larger aromaticity of the former. To our knowledge the relative stability of acenes and phenacenes in their lowest-lying triplet states (T1) has not been discussed yet. Using unrestricted density functional theory calculations, our results show that for the smallests members of the series, acenes in their T1 states are more stable than the corresponding phenacenes. However, when the number of the rings (n) involved increases, the energy difference is reduced and for n > 12, phenacenes become more stable than acenes in their T1 states. To rationalize this trend, we analyze the aromaticity of acenes and phenacenes using a set of aromaticity descriptors. We find that in the T1 states of both acenes and phenacenes, the outer rings form aromatic Clar π-sextets. In acenes, delocalization of spin density in the central rings leads to the preferred formation of the largest antiaromatic diradical. Resonant structures in the form of antiaromatic diradical Baird π-octadectets and π-tetradectets are the major contributors, while the smaller ones, such as π-doublets and π-sextets, contribute the least. In phenacenes, structures with diradical antiaromatic Baird π-sextets in some of the central rings contribute the most. These results are relevant to understand the (anti)aromaticity of larger polycyclic aromatic hydrocarbons in their triplet states
dc.description.sponsorship
R.B-G. is grateful for the financial support of FONDECYT Postdoctorado 3210037.
Powered@NLHPC. This research was partially supported by the supercomputing infrastructure of the NLHPC (ECM-02). M.S. acknowledges the financial support from the Ministerio de Economía y Competitividad of Spain (project CTQ2017-85341-P) and the Generalitat de Catalunya (project 2017SGR39)
dc.format.extent
9 p.
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
Royal Society of Chemistry (RSC)
dc.relation.isformatof
Versió postprint del document publicat a: https://doi.org/10.1039/D1CP01441B
dc.relation.ispartof
© Physical Chemistry Chemical Physics, 2021, vol. 23, p. 13574-13582
dc.relation.ispartofseries
Articles publicats (D-Q)
dc.rights
Tots els drets reservats
dc.source
Pino-Rios, Ricardo Báez-Grez, Rodrigo Solà i Puig, Miquel 2021 Acenes and phenacenes in their lowest-lying triplet states. Does kinked remain more stable than straight? Physical Chemistry Chemical Physics 23 13574 13582
dc.title
Acenes and phenacenes in their lowest-lying triplet states. Does kinked remain more stable than straight?
dc.type
info:eu-repo/semantics/article
dc.rights.accessRights
info:eu-repo/semantics/openAccess
dc.embargo.terms
2022-07-05T00:00:00Z
dc.date.embargoEndDate
info:eu-repo/date/embargoEnd/2022-07-05
dc.relation.projectID
info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTQ2017-85341-P/ES/AVANCES EN LA REACTIVIDAD DE FULLERENOS Y NANOTUBOS: ESTUDIOS TEORICO-EXPERIMENTALES DE CICLACIONES CATALIZADAS POR METALES DE TRANSICION/
dc.type.version
info:eu-repo/semantics/acceptedVersion
dc.identifier.doi
dc.identifier.idgrec
033637
dc.contributor.funder
dc.type.peerreviewed
peer-reviewed
dc.relation.FundingProgramme
dc.identifier.eissn
1463-9084