Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution
Abstract
By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly)benzenoid subunit(s) and weakly antiaromatic, or almost nonaromatic silacycle. Therefore, such systems are predicted to be globally aromatic in both the ground state and the first excited triplet state. Putting the silicon atom(s) into various positions of a hydrocarbon provides an opportunity to tune the singlet-triplet energy gaps. They depend on the global aromaticity degree which, in turn, depends on the type of aromatic carbocyclic subunit(s) and the extent of their aromaticity. On the basis of the set of studied compounds, some preliminary rules on how to regulate the extent of global, semiglobal and local aromaticity are proposed. The results of this work extend the importance of Hückel aromaticity concept to excited triplet stat...es which are usually characterized by the Baird type of (anti)aromaticity.
Keywords:
aromaticity / density functional calculations / fused-ring systems / silicon / triplet stateSource:
Chemistry. An Asian Journal, 2022, 17, 4, e202101261-Publisher:
- Wiley
Funding / projects:
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200168 (University of Belgrade, Faculty of Chemistry) (RS-MESTD-inst-2020-200168)
Note:
- Supplementary material: https://cherry.chem.bg.ac.rs/handle/123456789/4890
Related info:
- Referenced by
https://cherry.chem.bg.ac.rs/handle/123456789/4890
DOI: 10.1002/asia.202101261
ISSN: 1861-4728
PubMed: 34964285
WoS: 000743569800001
Scopus: 2-s2.0-85122896441
Collections
Institution/Community
Hemijski fakultet / Faculty of ChemistryTY - JOUR AU - Baranac-Stojanović, Marija AU - Stojanović, Milovan AU - Aleksić, Jovana PY - 2022 UR - http://cherry.chem.bg.ac.rs/handle/123456789/4889 AB - By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly)benzenoid subunit(s) and weakly antiaromatic, or almost nonaromatic silacycle. Therefore, such systems are predicted to be globally aromatic in both the ground state and the first excited triplet state. Putting the silicon atom(s) into various positions of a hydrocarbon provides an opportunity to tune the singlet-triplet energy gaps. They depend on the global aromaticity degree which, in turn, depends on the type of aromatic carbocyclic subunit(s) and the extent of their aromaticity. On the basis of the set of studied compounds, some preliminary rules on how to regulate the extent of global, semiglobal and local aromaticity are proposed. The results of this work extend the importance of Hückel aromaticity concept to excited triplet states which are usually characterized by the Baird type of (anti)aromaticity. PB - Wiley T2 - Chemistry. An Asian Journal T1 - Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution VL - 17 IS - 4 SP - e202101261 DO - 10.1002/asia.202101261 ER -
@article{ author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana", year = "2022", abstract = "By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly)benzenoid subunit(s) and weakly antiaromatic, or almost nonaromatic silacycle. Therefore, such systems are predicted to be globally aromatic in both the ground state and the first excited triplet state. Putting the silicon atom(s) into various positions of a hydrocarbon provides an opportunity to tune the singlet-triplet energy gaps. They depend on the global aromaticity degree which, in turn, depends on the type of aromatic carbocyclic subunit(s) and the extent of their aromaticity. On the basis of the set of studied compounds, some preliminary rules on how to regulate the extent of global, semiglobal and local aromaticity are proposed. The results of this work extend the importance of Hückel aromaticity concept to excited triplet states which are usually characterized by the Baird type of (anti)aromaticity.", publisher = "Wiley", journal = "Chemistry. An Asian Journal", title = "Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution", volume = "17", number = "4", pages = "e202101261", doi = "10.1002/asia.202101261" }
Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2022). Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. in Chemistry. An Asian Journal Wiley., 17(4), e202101261. https://doi.org/10.1002/asia.202101261
Baranac-Stojanović M, Stojanović M, Aleksić J. Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. in Chemistry. An Asian Journal. 2022;17(4):e202101261. doi:10.1002/asia.202101261 .
Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution" in Chemistry. An Asian Journal, 17, no. 4 (2022):e202101261, https://doi.org/10.1002/asia.202101261 . .