Fluorescent Silica Hybrid Film-Forming Materials Based on Salicylaldazine

Fluorescent film-forming materials were obtained by embedding salicylaldazine (SAA) in silica hybrids generated by sol–gel processes from different silane precursors in acid catalysis. Tuned local environments for the fluorophore were generated in the hosting network by modifying silica sols with organic groups through the co-condensation of tetraethylortosilicate (TEOS) and different alkoxysilanes hydrolysis products. The photophysical properties of the luminescent hybrid films were studied in direct relationship with structural, textural, and surface properties and based on interactions between SAA species and the silica hosting network. Film-forming materials were studied in order to determine differences in absorption and fluorescence emission due to the environments around the fluorophore. The variations recorded in the fluorescence emission spectra of the hybrid films were related to interactions established between the fluorophore species and their sterically hindered surroundings of the host hybrid silica, where free molecular motions are restricted. The influence of the type and amount of network modifier and of the fluorophore loading on the transparency of the films and fluorescence intensity was also investigated. The study carried out led to the elucidation of the necessary conditions for obtaining luminescent film-forming materials with high luminescence intensity and transparency useful for the design of new light concentrators.

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Novel Electric Responsive Columnar Liquid Crystals based on Perylene Tetra sec-alkyl Ester Derivatives

Australian Journal of Chemistry ◽

10.1071/ch13057 ◽

2013 ◽

Vol 66 (6) ◽

pp. 692 ◽

Cited By ~ 14

Author(s):

Lei Wang ◽

Qing Cui ◽

Xiao-Fang Chen ◽

Yang Li ◽

Zheng-Qiang Li ◽

...

Keyword(s):

Electric Field ◽

Molecular Orbital ◽

Indium Tin Oxide ◽

Photophysical Properties ◽

Mixed Solvents ◽

Fluorescence Emission ◽

Emission Spectra ◽

Mirror Image ◽

Alkyl Ester ◽

Fluorescence Emission Spectra

A series of novel perylene tetra sec-alkyl ester compounds were successfully designed and synthesised. The photophysical properties were investigated and the UV absorption and fluorescence emission spectra displayed a mirror-image relationship. The compound PS8 showed the highest fluorescent quantum yield, while the fluorescence of PS8 was quenched in the aggregated state in mixed solvents. Moreover, the electrochemical properties of the perylene derivatives were studied to determine the molecules’ highest occupied molecular orbital and lowest unoccupied molecular orbital levels by cyclic voltammetry. The most important result was that PS8 exhibited a columnar phase at room temperature and was responsive to an electric field. PS8 could perpendicularly orient to an applied electric field. In addition, highly oriented face-on alignment was achieved on indium tin oxide-covered glass by thermal annealing.

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Exploring the optoelectronic properties of a chromene-appended pyrimidone derivative for photovoltaic applications

Open Chemistry ◽

10.1515/chem-2019-0119 ◽

2019 ◽

Vol 17 (1) ◽

pp. 1167-1172

Author(s):

Mohammed A. Assiri

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Photophysical Properties ◽

Fluorescence Emission ◽

Emission Spectra ◽

Solvent Polarity ◽

Frontier Molecular Orbital ◽

Electronic Effects ◽

Fluorescence Emission Spectra ◽

Functional Theory

AbstractIn the present study, a chromene-appended pyrimidone derivative (PBA) has been synthesized in order to account for the relationship between chemical structure and charge transport properties. The optical properties of PBA were studied in different solvents; it displays a weak emission profile in polar protic solvents but is highly emissive in polar aprotic solvents. Quantum chemical approaches on this molecule were performed in detail to highlight the importance of and to better understand the structural and electronic effects of introducing substituted pyrimidone rings in a polyaromatic molecule to support the development of new optoelectronic and photovoltaic devices. We shed light on the frontier molecular orbital, electron injection, electronic coupling constant, light harvesting efficiency, and photophysical properties of PBA by using density functional theory and time domain density functional theory. The absorption spectra (λa) and fluorescence emission spectra (λf) were computed in different solvents (Methanol, Ethanol, Butanol, Hexane, Chloroform and DMF) at the TD-B3LYP/6-31G** and TD-PBE/6-31G** levels of theory, and it was determined that the TD-B3LYP/6-31G** level is more accurate in the reproduction of experimental λa and λf in various solvents. Furthermore, no significant effect was observed on the λa and λf by changing the solvent polarity.

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Incorporating two different chromophores onto a silicon atom: the crystal structure and photophysical properties of 9-{4-[(9,9-dimethyl-9H-fluoren-2-yl)dimethylsilyl]phenyl}-9H-carbazole

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229615002624 ◽

2015 ◽

Vol 71 (3) ◽

pp. 195-198

Author(s):

Ah-Rang Lee ◽

Won-Sik Han

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Density Functional ◽

Crystal Packing ◽

Photophysical Properties ◽

Fluorescence Emission ◽

Emission Spectra ◽

Fluorescence Emission Spectra ◽

Functional Theory ◽

Compound C

The crystal structure of the title bifunctional silicon-bridged compound, C35H31NSi, (I), has been determined. The compound crystallizes in the centrosymmetric space groupP21/c. In the crystal structure, the pairs of aryl rings in the two different chromophores,i.e.9-phenyl-9H-carbazole and 9,9-dimethyl-9H-fluorene, are positioned orthogonally. In the crystal packing, no classical hydrogen bonding is observed. UV–Vis absorption and fluorescence emission spectra show that the central Si atom successfully breaks the electronic conjugation between the two different chromophores, and this was further analysed by density functional theory (DFT) calculations.

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Synthesis and photophysical properties of some 6,6″-functionalized terpyridine derivatives

Open Chemistry ◽

10.2478/s11532-010-0146-4 ◽

2011 ◽

Vol 9 (2) ◽

pp. 218-223

Author(s):

Claudia Lar ◽

Gheorghe-Doru Roiban ◽

Romina Crăsneanu ◽

Ilişca Mihalca ◽

Elena Bogdan ◽

...

Keyword(s):

Photophysical Properties ◽

Fluorescence Emission ◽

Emission Spectra ◽

Chemical Derivatization ◽

Fluorescence Emission Spectra

AbstractThe synthesis and photophysical properties of several 6,6″ symmetrically substituted 4′-aryl-2,2′:6′,2″-terpyridine derivatives are reported herein. The UV-Vis spectra in acetonitrile as well as in dichloromethane show two intense bands in the UV areas 252–262 nm and 275–290 nm while the fluorescence emission spectra are only slightly influenced by chemical derivatization.

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Optical Properties and Zinc Nitride Thin Films Prepared Using Magnetron Reactive Sputtering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.940.11 ◽

2014 ◽

Vol 940 ◽

pp. 11-15

Author(s):

Jun Qin Feng ◽

Jun Fang Chen

Keyword(s):

Thin Films ◽

Band Gap ◽

Near Infrared ◽

Fluorescence Emission ◽

Emission Spectra ◽

Sem Images ◽

Fluorescence Emission Spectra ◽

Glass Substrates ◽

Zinc Nitride ◽

Direct Band

Zinc nitride films were deposited by ion sources-assisted magnetron sputtering with the use of Zn target (99.99% purity) on 7059 glass substrates. The films were characterized by XRD, SEM and EDS, the results of which show that the polycrystalline zinc nitride thin film can be grown on the glass substrates, the EDS spectrum confirmed the chemical composition of the films and the SEM images revealed that the zinc nitride thin films have a dense structure. Ultraviolet-visible-near infrared spectrophotometer was used to study the transmittance behaviors of zinc nitride thin films, which calculated the optical band gap by Davis Mott model. The results of the fluorescence emission spectra show the zinc nitride would be a direct band gap semiconductor material.

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Stress and Phase Transformation Phenomena in Oxide Films: Real-Time Spectroscopic Measurements

MRS Proceedings ◽

10.1557/proc-271-319 ◽

1992 ◽

Vol 271 ◽

Cited By ~ 3

Author(s):

Gregory J. Exarhos ◽

Nancy J. Hess

Keyword(s):

Phase Transformation ◽

Applied Pressure ◽

Oxide Films ◽

Fluorescence Emission ◽

Emission Spectra ◽

Film Deposition ◽

Optical Methods ◽

Fluorescence Emission Spectra ◽

Line Intensities ◽

Deposition Parameters

ABSTRACTIn situ optical methods are reviewed for characterization of phase transformation processes and evaluation of residual stress in solution-deposited metastable oxide films. Such low density films most often are deposited as disordered phases making them prone to crystallization and attendant densification when subjected to increased temperature and/or applied pressure. Inherent stress imparted during film deposition and its evolution during the transformation are evaluated from phonon frequency shifts seen in Raman spectra (TiO2) or from changes in the laser-induced fluorescence emission spectra for films containing rare earth (Sm+3:Y3Al5O12) or transition metal (Cr+3 :Al2O3) dopants. The data in combination with measured increases in line intensities intrinsic to the evolving phase are used to follow crystallization processes in thin films. In general, film deposition parameters are found to influence the crystallite ingrowth kinetics and the magnitude of stress and stress relaxation in the film during the transformation. The utility of these methods to probe crystallization phenomena in oxide films will be addressed.

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