A5009624113- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Organic Light-Emitting Diodes Research
- Luminescence and Fluorescent Materials
- Metal complexes synthesis and properties
- Liquid Crystal Research Advancements
- Magnetism in coordination complexes
- Metal-Catalyzed Oxygenation Mechanisms
- Organometallic Complex Synthesis and Catalysis
- Organic Electronics and Photovoltaics
- Photochemistry and Electron Transfer Studies
- Porphyrin and Phthalocyanine Chemistry
- Molecular Sensors and Ion Detection
- Perovskite Materials and Applications
- Lanthanide and Transition Metal Complexes
- Conducting polymers and applications
- Semiconductor materials and devices
- Molecular Junctions and Nanostructures
- Nanowire Synthesis and Applications
- Nanocluster Synthesis and Applications
- Synthesis and Biological Evaluation
- Chalcogenide Semiconductor Thin Films
- Advancements in Semiconductor Devices and Circuit Design
- 2D Materials and Applications
- Metalloenzymes and iron-sulfur proteins
Universidade de São Paulo
2025
Universidade Federal de Santa Catarina
2019-2024
Fundação de Amparo à Pesquisa e Inovação do Estado de Santa Catarina
2019-2020
Universidade Federal do Ceará
2004-2018
Instituto de Cerámica y Vidrio
2003
Universidad Autónoma de Madrid
2003
In this work, we present a general method for predicting phosphorescence rates and spectra molecules using time-dependent density functional theory (TD-DFT) path integral approach the dynamics that relies on harmonic oscillator approximation nuclear movement. We first discuss involved in including spin-orbit coupling (SOC) among singlet triplet excited states then how to compute corrected transition dipole moments rates. investigate dependence of these some TD-DFT parameters, such as nature...
Abstract The dehydrating cyclotrimerization of 1‐tetralone in the presence titanium tetrachloride at high temperatures leads to homotruxene, a nonplanar arene which twist angles between its three outer benzene rings and central are stabilized by ethylene bridges. This non‐planar configuration allows for pronounced spin–orbit coupling triplet energy, leading room‐temperature phosphorescence air with lifetime 0.38 s quantum yield 5.6 %, clearly visible human eye after switching off excitation....
Delayed emission (DF) of fluorescence is generally observed either in solution or the crystalline state. In latter, well‐defined intermolecular interactions may play a significant role defining characteristics. Here, we present trialkoxy‐homotruxene that liquid at room temperature and compare its behavior with analog containing same π‐electron system. The DF due to triplet‐triplet annihilation (TTA) persists low temperatures (90 K). Accompanied by slightly shorter phosphorescence lifetimes,...
Twisted π-systems investigation showed a very unusual HAE, influencing independently the ISC and dual phosphorescence emission, one being persistent at room temperature visible by eye in powder.
In this work, we describe how Resonant Raman (RR) spectra can be predicted with good accuracy using the path integral formulation for harmonic oscillator, including Herzberg-Teller and Duschinsky rotation effects. particular, will focus on approximations to make these calculations more efficient expand current methodology include overtones combination bands in final prediction. After outlining theory, explain it made into a black-box method discuss that rely its intrinsic parameters. It is...
Cu(<sc>i</sc>) complexes without the expected heavy atom effect to enhance spin–orbit coupling matrix elements, but with reduced photoluminescence lifetime.
Abstract The dehydrating cyclotrimerization of 1‐tetralone in the presence titanium tetrachloride at high temperatures leads to homotruxene, a nonplanar arene which twist angles between its three outer benzene rings and central are stabilized by ethylene bridges. This non‐planar configuration allows for pronounced spin–orbit coupling triplet energy, leading room‐temperature phosphorescence air with lifetime 0.38 s quantum yield 5.6 %, clearly visible human eye after switching off excitation....
Most organic room-temperature phosphorescence (RTP) emitters do not show their RTP in solution. Here, we incorporated sulfur-containing thiophene bridges between the donor and acceptor moieties D3 A-type tristriazolotriazines (TTTs). The inclusion increased spin-orbit coupling associated with radiative T1 →S0 pathway, allowing to be observed solution for all compounds, likely assisted by protection of emissive TTT-thiophene core from environment bulky peripheral donors.
The electronic band structure of cubic HfO2 is calculated using an ab initio all-electron self-consistent linear augmented plane-wave method, within the framework local-density approximation and taking into account full-relativistic contributions. From structure, carrier effective masses complex dielectric function are obtained. Γ-isotropic heavy light electron shown to be several times heavier than tunneling mass measured recently. imaginary part ϵ2(ω) in good agreement with experimental...
Abstract Luminescent copper(I) complexes presenting thermally activated delayed fluorescence (TADF) have drawn attention as emitters for organic light emitting diodes (OLEDs). While the majority of ligands used nitrogen donor atoms, in this work, we report synthesis and characterization three with diimine ligand 1,10‐phenanthroline aminophosphine‐derived containing piperazine N , N’ ‐dimethylethylenediamine to evaluate their effect into emission properties. The photophysical studies a...
Triply phenanthryl- and tetrahelicenyl-substituted triazine-hexaalkyl esters with short alkyl chains show glass transitions conveniently above room temperature within the hexagonal columnar liquid crystalline state, resulting in a solid order at temperature. As mesophase is easily aligned director perpendicular to substrate, such glassy matrices are aimed for orientation of guest emitters, obtain anisotropic emission. A condition face-on alignment on substrates attainable melting clearing...
Luminescent boron(III) complexes have recently been employed as emitters in organic light‐emitting diodes (OLEDs) with reasonable success. They are easy to prepare and sufficiently stable be used such devices, being of great interest a simple molecular emissive layer. Although for this class all colors already reported, highly efficient blue applications solution processed devices still pose challenge. Here, we report the design, synthesis, characterization new boron based on...
Abstract Catecholase activity of dicopper(II) complexes containing different numbers chelate members in the pyridine groups ligand was studied to identify a functional model for copper enzyme catechol oxidase. Complexes [Cu II (μ‐OH)Cu (L 1 )](ClO 4 ) ( ), 2 and 3 were synthesized characterized by elemental analysis, FTIR, UV–Vis spectroscopy, mass spectrometry, electrochemistry. Their catalytic oxidation 3,5‐di‐ tert‐ butylcatechol determined. Changing number rings altered activity. Complex...
Herein, we report the synthesis and characterization of fluorophores containing a 2,1,3-benzoxadiazole unit associated with π-conjugated system (D-π-A-π-D). These new in solution exhibited an absorption maximum at around ~419 nm (visible region), as expected for electronic transitions π-π* type (ε ~2.7 × 107 L mol-1 cm-1), strong solvent-dependent fluorescence emission (ΦFL ~0.5) located bluish-green region. The Stokes' shift these compounds is ca. 3,779 cm-1, which was attributed to...
The catalytic properties of three copper complexes, [Cu(en)2](ClO4)2 (1), [Cu(amp)2](ClO4)2, (2) and [Cu(bpy)2](ClO4)2 (3) (where en = ethylenediamine, amp 2-aminomethylpyridine bpy 2,2′-bipyridine), were explored upon the oxidation benzyl alcohol (BnOH). Maximized conversions substrates to their respective products obtained using a multivariate analysis approach, powerful tool that allowed multiple variables be optimized simultaneously, thus creating more economical, fast effective...
Abstract Whereas their para homologs are not mesogenic, the disk‐shaped triphenyltriazine meta‐trialkylesters obtained via trimerization of 3‐cyanobenzoic alkylester, which configurationally more flexible, exhibit a monotropic nematic mesophase. Introduction fluorine atoms into alkyl chains or phenyl moieties leads to appearance an enantiotropic columnar If is introduced both in and moieties, only mesophase remains. Fluorination either aromatic core, but both, appears thus as simple means...
The radiative transitions in P- and B-doped Si nanocrystals are investigated by means of first-principle calculations. Using a three-level model, we show that the lifetimes oscillator strengths between conduction impurity bands, as well valence bands strongly affected position. On other hand, direct conduction-to-valence band decay is practically unchanged due to presence impurity. In addition, emission intensity P(B)-doped with impurities positioned surface (anywhere) higher (lower) than...