Computational study of the geometry and electronic structure of triazolephthalocyanines

Iglesias, Rodrigo S.; Nicolau, Mónica; Cabezón, Beatriz; Stéfani, Valter; Torres, Tomás; Livotto, Paolo Roberto

doi:10.1039/b107790m

Cited by 12 publications

(10 citation statements)

References 38 publications

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“…These properties include, as well, photosensitivity, flexible structural modification and strong absorbance in the 600–800 nm region [ 4 , 7 , 8 ]. Also, it is known that the bandgap energy between HOMO (Highest Occupied Molecular) and LUMO (Lowest Unoccupied Molecular Orbital) can be tuned for these materials, as well as for photoluminescence (PL) and light absorption [ 5 , 6 , 9 ]. MPcs, formed by certain type of substituents or functional groups in their structure, present great chemical stability and are insoluble in most solvents [ 10 ], but not in water [ 10 , 11 , 12 ].…”

Section: Introductionmentioning

confidence: 99%

New Development of Membrane Base Optoelectronic Devices

et al. 2017

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It is known that one factor that affects the operation of optoelectronic devices is the effective protection of the semiconductor materials against environmental conditions. The permeation of atmospheric oxygen and water molecules into the device structure induces degradation of the electrodes and the semiconductor. As a result, in this communication we report the fabrication of semiconductor membranes consisting of Magnesium Phthalocyanine-allene (MgPc-allene) particles dispersed in Nylon 11 films. These membranes combine polymer properties with organic semiconductors properties and also provide a barrier effect for the atmospheric gas molecules. They were prepared by high vacuum evaporation and followed by thermal relaxation technique. For the characterization of the obtained membranes, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to determine the chemical and microstructural properties. UV-ViS, null ellipsometry, and visible photoluminescence (PL) at room temperature were used to characterize the optoelectronic properties. These results were compared with those obtained for the organic semiconductors: MgPc-allene thin films. Additionally, semiconductor membranes devices have been prepared, and a study of the device electronic transport properties was conducted by measuring electrical current density-voltage (J-V) characteristics by four point probes with different wavelengths. The resistance properties against different environmental molecules are enhanced, maintaining their semiconductor functionality that makes them candidates for optoelectronic applications.

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Section: Introductionmentioning

confidence: 99%

New Development of Membrane Base Optoelectronic Devices

et al. 2017

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“…On the other hand, theoretical calculations on triazolephthalocyanines are currently available. 10 Since triazoleporphyrazines are of great interest as a new type of intrinsically noncentrosymmetrical porphyrazine analogue, we report here a theoretical investigation of the electronic structure of the macrocycle, with emphasis on its aromaticity.…”

Section: Introductionmentioning

confidence: 99%

Aromaticity in tautomers of triazoleporphyrazine

Islyaikin

Ferro

Vega

2002

J. Chem. Soc., Perkin Trans. 2

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The effect of tautomerism on the aromaticity was studied for the free base triazoleporphyrazine at the Density Functional Theory level, using double-zeta double polarized basis sets. The porphyrazine (1), the three tautomers (2a, 2b and 2c) as well as the Ni complex (3) of triazoleporphyrazine were examined. Two independent aromaticity criteria, the geometry-based index HOMA and the magnetic properties-based index NICS, were used to estimate the aromaticity of the complete and selected fragments of the above compounds. Results show that structure 2a, which has the H atom in position 1 of the triazole ring, has low aromaticity, although it contains structural fragments with large conjugation. The aromatic character of both tautomers 2b and 2c is similar to that of both the porphyrin and the porphyrazine. The central ring contour was found to be the most aromatic part of the triazoleporphyrazine tautomers. Occupancy of the central position of the macrocycle cavity of the triazoleporphyrazine by a metal atom increases the aromaticity of the macrocycle as a whole, but reduces the conjugation of the central cross sub-unit. In conclusion, both criteria can be used confidently for evaluating the aromaticity for the studied systems.

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“…2. Its feature is similar to those of metal phthalocyanine molecules [17][18][19][20]. The farthest red region of the spectrum is located at Q 1 (0,0) band (λ = 691 nm) with extinction coefficient of ε 691nm = 1.31 × 10 4 M −1 cm −1 .…”

Section: Resultsmentioning

confidence: 52%

“…Usually, UV-Vis spectra of phthalocyanines (Pcs) demonstrate typical electronic spectra with two strong absorption bands known as B and Q bands [17][18][19]. The B band in the UV region at 300-400 nm is attributed to deep π-π* transition from HOMO to LUMO of the Pc [20][21][22] with a small contribution from n-π* transition, whereas the Q band in the visible region at 600-750 nm originates from the less deep π-π* transition of HOMO to LUMO of the Pc (−2).…”

Section: Resultsmentioning

confidence: 99%

Resonance energy transfer and competing processes in donor–acceptor of sodium zinc (II)-2,9,16,23-phthalocyanine tetracarboxylate molecule

Al-Omari

2016

J Biol Phys

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An important issue that should be taken into consideration when applying the molecules in photodynamic therapy (PDT) of cancer is the occurrence of homo-resonance energy transfer process between them. We have determined the probability of energy transfer for sodium zinc (II)-2,9,16,23-phthalocyanine tetracarboxylate (ZnPc(COONa) 4 ) molecules in aqueous NaOH solution. The homo-quenching effect of the molecule was also measured by calculating the diffusion controlled bimolecular rate constant of k q = 6.5 × 10 9 M −1 s −1 , which did not show a significant competition with the rate constant of homo-resonance energy transfer process at the applied concentration of the molecules (6 μM). The Förster radius (R 0 ) for ZnPc(COONa) 4 molecules was calculated to be 42 Å. The availability of these calculations should facilitate the potential application of ZnPc(COONa) 4 molecule as an anticancer drug in PDT.

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Computational study of the geometry and electronic structure of triazolephthalocyanines

Cited by 12 publications

References 38 publications

New Development of Membrane Base Optoelectronic Devices

New Development of Membrane Base Optoelectronic Devices

Aromaticity in tautomers of triazoleporphyrazine

Resonance energy transfer and competing processes in donor–acceptor of sodium zinc (II)-2,9,16,23-phthalocyanine tetracarboxylate molecule

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