Vibrational spectroscopy and quantum chemical studies of 1,6,7,12,13,18-hexaazatrinaphthylene and related compounds

Gordon, Keith C.; David, Gabrielle; Walsh, Timothy J.

doi:10.1016/j.saa.2008.07.039

Cited by 15 publications

(8 citation statements)

References 15 publications

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“…The major two band regions observed in the spectra at 416–428 nm and 334–343 nm for ( 2 C10 ) and at 427–437 nm and 302–344 for 1 C10 appeared to consist of two intense π→π* transitions due to the increased conjugation in HATN system. Similar observations have been made in the case of the HATN analogues …”

Section: Resultssupporting

confidence: 86%

Long‐Range Self‐Assembly of an Electron‐Deficient Hexaazatrinaphthylene with Out‐of‐Plane Substituents

et al. 2019

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The unprecedented time‐dependent long‐range supramol‐ecular assembly of electron‐deficient hexaazatrinaphthylene (HATN) core based on peripheral crowding with three out‐of‐plane cyclic ketals is reported. The single‐crystal X‐ray structure of the diethyl derivative provided detailed information as to how four molecules in a repeating unit were packed in order to avoid steric crowding of the out‐of‐plane cyclic ketal side chain, providing locking and fastening for stabilizing the self‐assembled structure. The polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) did not instantaneously show any phase transition upon the cooling process. To our surprise, POM images showed a nucleation of spherulite up to 100 μm after 24 hour later. X‐ray diffraction data further confirmed that these soft crystal formed a hexagonal‐like crystal. The long‐range self‐assembly of the new material showed a slight red shift in the UV‐vis absorption spectra and further substantiated by computational method.

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Section: Resultssupporting

confidence: 86%

Long‐Range Self‐Assembly of an Electron‐Deficient Hexaazatrinaphthylene with Out‐of‐Plane Substituents

et al. 2019

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“…Resonance Raman data and eigenvector diagrams for BTD-TPA are shown in Figure while the remaining spectra are shown in Figure S7. Resonance Raman spectroscopy is an effective tool for identifying active chromophores as a result of region specific band enhancement that occurs coincident with ground → excited state distortions. − When band resonance enhancement is monitored as a function of excitation wavelength, the nature of transitions can be probed. For this series of compounds, emission precludes data collection to the red of 448–491 nm, depending on the compound.…”

Section: Resultsmentioning

confidence: 99%

Walking the Emission Tightrope: Spectral and Computational Analysis of Some Dual-Emitting Benzothiadiazole Donor–Acceptor Dyes

et al. 2018

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The synthesis, spectroscopic characterization, and computational modeling of seven benzo[ c][2,1,3]thiadiazole-based donor-acceptor dyes is reported. Using a range of linker units, it is possible to alter the lowest energy transition in terms of intensity (from 8000 to 25000 L mol cm) and wavelength (from 350 to 430 nm). Resonance Raman spectroscopy was used in concert with DFT calculations to indicate that the linker unit participates in charge transfer processes. In each compound the excited state behavior appears to be primarily described by a BTD-Linker-TPA state. Stokes shift versus solvent parameter gradients are on the order of 15000 cm, indicating Δμ values are large. Dual emission is observed in six of the seven compounds and it can be modulated as a function of solvent. TD-DFT calculations, including excited state optimizations (linear response and state specific), indicate that the lowest energy emission is charge transfer in character. The high energy emissive state is assigned as n-π*. In nonpolar solvents, only the low energy charge transfer emission band is observed and this band generally has a high quantum yield (Φ ≈ 0.9). For compounds with phenyl and triazolyl linkers, in polar solvents only the high energy n-π* emission is observed. The high energy n-π* emission has a low quantum yield regardless of solvent.

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“…In this work we adopted the scaling factor reported by Irikura et al [24] for the B3LYP/6-31G* level (0.9594), derived by a leastsquares fitting procedure of experimental and calculated harmonic wavenumber values for a series of 41 common organic compounds. The use of scaling techniques generally reduces the deviation between experimental and calculated data, as demonstrated by the satisfactory results for some PAH derivatives [17,18,[25][26][27][28][29][30][31]. The simulated vibrational spectra were represented by convoluting the calculated wavenumber values with pure Lorentzian band shapes using a full-width at half-maximum of 10 cm -1 , as usually adopted in the literature [32][33][34][35].…”

Section: Ir and Raman Spectramentioning

confidence: 99%

Physicochemical characterization of environmental mutagens: 3-nitro-6-azabenzo[a]pyrene and its N-oxide derivative

Alparone

Librando

2012

Monatsh Chem

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Molecular geometries, nucleus independent chemical shifts, electronic, infrared and Raman spectra, vertical ionization energy and electron affinity, dipole moment, and electronic polarizabilities of 3-nitro-6-azabenzo[a]pyrene and its N-oxide derivative were calculated for the gas phase using semiempirical and density functional theory. The influence of the N-oxidation on structural, electronic, and spectroscopic properties is discussed. The infrared spectral region around 1,300 cm -1 involving the azabenzene N-O and the NO 2 stretching vibrations is potentially useful to distinguish 3-nitro-6-azabenzo[a]pyrene from its N-oxide derivative. The calculated vertical ionization energy for 3-nitro-6-azabenzo[a]pyrene N-oxide is smaller than that of its parent compound, whereas the vertical electron affinity is higher in agreement with the experimental electrochemical reduction potentials. Both dipole moment and polarizability increase on passing from 3-nitro-6-azabenzo[a]pyrene to its N-oxide derivative, the contribution from the N-O bond formation being substantial. The electric property enhancements are explained through atomic charges and spectral shifts. Present results support the higher mutagenic activity for the N-oxide derivative in comparison with its parent compound.

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Vibrational spectroscopy and quantum chemical studies of 1,6,7,12,13,18-hexaazatrinaphthylene and related compounds

Cited by 15 publications

References 15 publications

Long‐Range Self‐Assembly of an Electron‐Deficient Hexaazatrinaphthylene with Out‐of‐Plane Substituents

Long‐Range Self‐Assembly of an Electron‐Deficient Hexaazatrinaphthylene with Out‐of‐Plane Substituents

Walking the Emission Tightrope: Spectral and Computational Analysis of Some Dual-Emitting Benzothiadiazole Donor–Acceptor Dyes

Physicochemical characterization of environmental mutagens: 3-nitro-6-azabenzo[a]pyrene and its N-oxide derivative

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