Expanded Azahelicenes with Large Dissymmetry Factors

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(18)

Published: Feb. 29, 2024

Abstract Expanded azahelicenes, as heteroanalogues of helically chiral helicenes, hold significant potential for chiroptical materials. Nevertheless, their investigation and research have remained largely unexplored. Herein, we present the facile synthesis a series expanded azahelicenes NHn ( n =1–5) consisting 11, 19, 27, 35, 43 fused rings, mainly by Suzuki coupling followed Bi(OTf) 3 ‐mediated cyclization vinyl ethers. The structures NH2 , NH3 NH4 were confirmed through X‐ray crystallography analysis, P )‐ M enantiomers also isolated with high performance liquid chromatography. exhibit large absorption (abs) luminescence (lum) dissymmetry factors, | g abs max =0.044; lum =0.003 =0.048; |=0.014 =0.043; =0.021 which are superior to respective all‐carbon analogues.

Language: Английский

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Impact of helical elongation of symmetric oxa[n]helicenes on their structural, photophysical, and chiroptical characteristics

Chirality, Journal Year: 2024, Volume and Issue: 36(5)

Published: May 1, 2024

Abstract The adjustment of the main helical scaffold in helicenes is a fundamental strategy for modulating their optical features, thereby enhancing potential diverse applications. This work explores influence elongation (n = 5–9) on structural, photophysical, and chiroptical features symmetric oxa[ n ]helicenes. Crystal structure analyses revealed structural variations with extension, impacting torsion angles, pitch, packing arrangements. Through theoretical investigations using density functional theory (DFT) calculations, impact extension aromaticity, planarity distortion, heightened chiral stability were discussed. Photophysical studied through spectrophotometric analysis, insights gained time‐dependent DFT (TD‐DFT) calculations. Following resolution via high‐performance liquid chromatography (HPLC), properties both enantiomers oxa[7]helicene oxa[9]helicene investigated. A slight variation ]helicenes from [7] to [9] induced an approximately three‐fold increase dissymmetry factors biggest values of| g lum | (2.2 × 10 −3 ) compared to| |of (0.8 ), findings discussed supported by TD‐DFT

Language: Английский

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Massively parallel GPU enabled third-order cluster perturbation excitation energies for cost-effective large scale excitation energy calculations

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 158(14)

Published: March 13, 2023

We present here a massively parallel implementation of the recently developed CPS(D-3) excitation energy model that is based on cluster perturbation theory. The new algorithm extends one in Baudin et al. [J. Chem. Phys., 150, 134110 (2019)] to leverage multiple nodes and utilize graphical processing units for acceleration heavy tensor contractions. Furthermore, we show extended scales efficiently with increasing amounts computational resources code enables calculations large molecular systems low time-to-solution. More specifically, over 100 atoms 1000 basis functions are possible few hours wall clock time. This establishes energies as computationally efficient alternative those obtained from coupled-cluster singles doubles model.

Language: Английский

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CPL calculations of [7]helicenes with alleged exceptional emission dissymmetry values

Journal of Materials Chemistry C, Journal Year: 2023, Volume and Issue: 11(31), P. 10474 - 10482

Published: Jan. 1, 2023

Probing the Chiroptical Enigma : compelling evidence calling for a re-evaluation of experimental g lum values two 1,1′-bitriphenylene-based [7]helicenes is obtained by TD-DFT simulations with advanced state-specific solvation effects.

Language: Английский

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Expanded Azahelicenes with Large Dissymmetry Factors

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(18)

Published: Feb. 29, 2024

Abstract Expanded azahelicenes, as heteroanalogues of helically chiral helicenes, hold significant potential for chiroptical materials. Nevertheless, their investigation and research have remained largely unexplored. Herein, we present the facile synthesis a series expanded azahelicenes NHn ( n =1–5) consisting 11, 19, 27, 35, 43 fused rings, mainly by Suzuki coupling followed Bi(OTf) 3 ‐mediated cyclization vinyl ethers. The structures NH2 , NH3 NH4 were confirmed through X‐ray crystallography analysis, P )‐ M enantiomers also isolated with high performance liquid chromatography. exhibit large absorption (abs) luminescence (lum) dissymmetry factors, | g abs max =0.044; lum =0.003 =0.048; |=0.014 =0.043; =0.021 which are superior to respective all‐carbon analogues.

Language: Английский

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Modeling Absorption and Emission Spectroscopies of Symmetric and Asymmetric Azaoxahelicenes in Vacuum and Solution

The Journal of Physical Chemistry A, Journal Year: 2022, Volume and Issue: 126(37), P. 6467 - 6472

Published: Sept. 12, 2022

Helicenes are of general interest due to the significant chiral signals in both absorption- and emission-based spectroscopy. Herein, spectroscopic properties four recently synthesized azaoxahelicenes studied using density functional theory methods. The have 7, 9, 10, 13 units one two complete turns structure. UV-vis absorption electronic circular dichroism spectra determined vacuum solution explicit solvation through a combined molecular dynamics/polarizable embedding framework. Additionally, emission circularly polarized luminescence based on vibronic calculations. resulting good agreement with experimentally available data, highlighting that systems can be modeled computationally such reliable predictions made for yet synthesized.

Language: Английский

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Virtual Issue on Chiroptical Spectroscopy

The Journal of Physical Chemistry A, Journal Year: 2023, Volume and Issue: 127(37), P. 7677 - 7681

Published: Sept. 21, 2023

ADVERTISEMENT RETURN TO ISSUEEditorialNEXTVirtual Issue on Chiroptical SpectroscopyPatrick H. Vaccaro*Patrick VaccaroDepartment of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States*[email protected]More by Patrick Vaccarohttps://orcid.org/0000-0001-7178-7638 and Yunjie Xu*Yunjie XuDepartment University Alberta, Edmonton, Canada T6G 2G2*[email Xuhttps://orcid.org/0000-0003-3736-3190Cite this: J. Phys. Chem. A 2023, 127, 37, 7677–7681Publication Date (Web):September 21, 2023Publication History Received17 August 2023Published online21 September inissue 21 2023https://pubs.acs.org/doi/10.1021/acs.jpca.3c05566https://doi.org/10.1021/acs.jpca.3c05566editorialACS PublicationsCopyright © Published 2023 American Chemical Society. This publication is available under these Terms Use. Request reuse permissions free to access through this site. Learn MoreArticle Views728Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum full text article downloads since November 2008 (both PDF HTML) across all institutions individuals. These metrics regularly updated reflect usage leading up last few days.Citations number other articles citing article, calculated Crossref daily. Find more information about citation counts.The Altmetric Attention Score a quantitative measure attention that research has received online. Clicking donut icon will load page at altmetric.com with additional details score social media presence for given article. how calculated. Share Add toView InAdd Full Text ReferenceAdd Description ExportRISCitationCitation abstractCitation referencesMore Options onFacebookTwitterWechatLinked InRedditEmail (968 KB) Get e-AlertscloseSUBJECTS:Chirality,Circular dichroism spectroscopy,Molecular interactions,Molecular structure,Spectroscopy e-Alerts

Language: Английский

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High-Performance Circular Polarization Multiple-Resonance TADF Molecules with Enhanced Long-Range Charge Transfer Based on Chiral Paracyclophane

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: unknown, P. 340 - 348

Published: Dec. 27, 2024

Circularly polarized multiple-resonance thermally activated delayed fluorescence (CP-MR-TADF) materials have received widespread attention in recent years, but it remains a formidable challenge to design high-performance CP-MR-TADF emitters concurrently exhibiting high quantum efficiency, narrowband emission, and dissymmetry factor (g). Here, we perform an in-depth theoretical investigation on the based [2.2] paracyclophane (pCp) derivatives. The MR-based with enhanced long-range charge transfer (LRCT) characteristics upon excitation show increased g values owing coaxial dominated transition components of electric dipole moment (TEDM) magnetic (TMDM) inevitably result loss emission performance. Furthermore, newly designed molecules by fusing peripheral benzene units MR cores within planar chiral pCp bridge maintain emissions exhibit order 1 × 10–3. These findings rich physical insights structure–performance relation paracyclophane-based should provide important clues for designing materials.

Language: Английский

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Theoretical Investigation of the E/Z Photoisomerization Pathway in 1-(2-Pyrrolyl)-2-(2-thienyl)ethylene

The Journal of Physical Chemistry A, Journal Year: 2023, Volume and Issue: 127(27), P. 5673 - 5682

Published: July 3, 2023

Molecular-level understanding of photochemistry in simple vinylene-linked systems such as ethylene and stilbene has been a major area research. However, the effect replacing two benzene rings by five-membered heterocyclic rings, thiophene pyrrole, is yet to be reported. In present theoretical study, our aim illustrate photoinduced processes thiophene-pyrrole system. Computational studies are carried out at RI-MP2/RI-ADC(2)/cc-pVTZ level explore different isomerization pathways. Minimum-energy conical intersection (MECI) structures categorized into types: closed-ring twisted-pyramidalized structures. Relaxation through former MECIs accessible only from cis isomers. latter inaccessible due high energy barriers along linear interpolation internal coordinate paths.

Language: Английский

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