Preparation, structure, and electrochemistry of porphyrinato titanium (IV) benzenedithiolates with a trithiole ring, a dithiin ring, and two 2-cyanoethylthio groups

2018 ◽  
Vol 22 (01n03) ◽  
pp. 157-164
Author(s):  
Takeshi Kimura ◽  
Yusuke Muraoka ◽  
Kaori Amano ◽  
Toshiyuki Fujio ◽  
Takao Nishikawa ◽  
...  
Keyword(s):  
Gold Electrode ◽  
Chemical Shifts ◽  
Energy Levels ◽  
Dft Method ◽  
Similar Reaction ◽  
X Ray Crystallography ◽  
Cesium Hydroxide ◽  
Homo And Lumo ◽  
Related Compounds ◽  
Homo And Lumo Energy

The reaction of tetra([Formula: see text]-tolyl)porphyrinato titanium (IV) oxide (2) with 4,7-diethyl-5,6-dimercaptobenzo[1,2,3] trithiole (3a) produced the corresponding titanium (IV) complex, tetra([Formula: see text]-tolyl)porphyrinato titanium (IV) trithiolobenzenedithiolate (4a), fused with a trithiole ring. Related compounds 4b and 4c were prepared by a similar reaction of 2 with 5,8-diethyl-6,7-dimercaptobenzo[1,4]dithiin (3b) and 3,6-diethyl-4,5-dimercapto-1,2-bis(2-cyanoethylthio)benzene (3c). The structure of 4b was determined by X-ray crystallography. Compound 4c was further treated with cesium hydroxide to produce the corresponding dithiolate anion 4c2S, which was deposited on the gold electrode. The electrochemical property of the gold electrode was determined by cyclic voltammetry. The structure of simplified model compound 4b[Formula: see text] was optimized using the DFT method with the Gaussian 09 program. The optimized structure was utilized to calculate the NMR chemical shifts, the HOMO and LUMO energy levels, and the electronic transition in the absorption spectrum.

Properties of Fluorene Derivatives: DFT Investigation

2012 ◽  
Vol 532-533 ◽  
pp. 97-100
Author(s):  
Bo Wei Chen ◽  
Guan Jun Chang ◽  
Lin Zhang
Keyword(s):  
Electronic Structure ◽  
Absorption Spectra ◽  
Electronic Structures ◽  
Energy Levels ◽  
Dft Method ◽  
Semiconductor Materials ◽  
Density Functions ◽  
Lumo Energy ◽  
Homo And Lumo ◽  
Homo And Lumo Energy

Fluorene derivatives are typical semiconductor materials. The electronic structures of Fluorene derivatives were successfully investigated by density functions theory (DFT). Furthermore, the HOMO and LUMO energy levels will be changed owing to the introduction of some aliphatic chains in the fluorene. So through theoretical investigation of electronic structure and molecule orbit by the DFT method, the variational UV-vis absorption spectra of fluorene derivatives due to variational levels were explained.

scholarly journals The Effect of Acceptor Structure on Emission Color Tuning in Organic Semiconductors with D–π–A–π–D Structures

Nanomaterials ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 1179 ◽  
Author(s):  
Przemyslaw Ledwon ◽  
Gabriela Wiosna-Salyga ◽  
Marian Chapran ◽  
Radoslaw Motyka
Keyword(s):  
Organic Semiconductors ◽  
Fluorescence Spectra ◽  
Near Infrared ◽  
Energy Levels ◽  
Light Emitting ◽  
Emission Color ◽  
Donor Acceptor ◽  
Homo And Lumo ◽  
Emission Quenching ◽  
Homo And Lumo Energy

A series of novel donor–acceptor D–π–A–π–D compounds were synthesized and characterized in order to determine the influence of different acceptor units on their properties. The introduction of acceptor moieties had a direct impact on the HOMO and LUMO energy levels. Fluorescence spectra of compounds can be changed by the choice of an appropriate acceptor and were shifted from the green to the near-infrared part of spectra. Due to observed concentration induced emission quenching, the green exciplex type host was used to evaluate the potential of synthesized molecules as emitters in organic light emitting diodes (OLEDs).

scholarly journals Synthesis and Characterisation of Novel Thiophene Based Azomethine Polymers and Study of Their Liquid Crystalline, Electrochemical and Optoelectronic Properties

2017 ◽  
Vol 25 (5) ◽  
pp. 345-362 ◽  
Author(s):  
Omer Yasin Al-Janabi ◽  
Peter J.S. Foot ◽  
Emaad Taha Al-Tikrity ◽  
Peter Spearman
Keyword(s):  
Cyclic Voltammetry ◽  
Liquid Crystalline ◽  
Room Temperature ◽  
Energy Levels ◽  
Band Gaps ◽  
Gas Liquid Chromatography ◽  
Lumo Energy ◽  
Chemical Structures ◽  
Homo And Lumo ◽  
Homo And Lumo Energy

This work reports the synthesis, structural characterisation, liquid crystallinity, luminescence and electroluminescence of novel thiophene azomethine polymers. The polymers under study were prepared via oxidative polymerisation of four novel monomers at room temperature using iron (III) chloride. The chemical structures of the prepared monomers and polymers were confirmed by infrared and 1H and 13CNMR spectroscopy. Molecular masses were determined for monomers and polymers by gas/liquid chromatography-mass spectrometry (GC/LC-MS) and by gel-permeation (size exclusion) chromatography (SEC), respectively. Thermal stability studies of the prepared materials were achieved by thermogravimetric analysis (TGA), and the onset of weight loss To and the endset Tmax were calculated from the thermograms. Liquid crystalline mesophases and phase changes of the monomers and polymers were studied by differential scanning calorimetry (DSC) and polarised optical microscopy (POM), and the glass transition temperatures Tg of the polymers were determined from the DSC curves. The electrochemical band gaps, HOMO and LUMO energy levels were measured by cyclic voltammetry. UV-visible absorption-emission spectra (liquid and solid films) of the polymers were obtained at room temperature with different solvents. Optical band gaps were calculated from the absorption edges, and were in good agreement with those estimated from cyclic voltammetry. Mixing the polymers with lanthanide salts such as EuCl3 and YbCl3 gave modified fluorescence, and the light emitted was much more intense than that from the pure polymers. Polymer based light-emitting diodes (PLEDs) were fabricated by spin coating, and their current-voltage characteristics were measured. In preliminary work, the polymer devices were found to produce electroluminescent spectra similar to the PL spectra of the corresponding samples. Molecular modelling studies were performed both on polymer segments and monomer molecules; the absorption spectra of the prepared polymers, HOMO and LUMO energy levels were calculated with ZINDO using AMI geometry optimisation.

Functionalized Rosette Nanotubes as Novel Electron Donor Materials for Solution-Processed Organic Photovoltaics

2015 ◽  
Vol 1737 ◽  
Author(s):  
Liang Shuai ◽  
Venkatakrishnan Parthasarathy ◽  
Jae-Young Cho ◽  
Takeshi Yamazaki ◽  
Rachel L. Beingessner ◽  
...  
Keyword(s):  
Electron Donor ◽  
Organic Photovoltaics ◽  
Energy Levels ◽  
Spectroscopic Techniques ◽  
Solution Processed ◽  
Rosette Nanotubes ◽  
Self Assembling ◽  
Hybrid Molecules ◽  
Homo And Lumo ◽  
Homo And Lumo Energy

ABSTRACTTwo self-assembling twin guanine-cytosine (G∧C) hybrid molecules featuring porphyrin (TPPO-(G∧C)2) and oligothiophene groups (6T-(G∧C)2) were synthesized. In organic solution, these molecules self-assemble into one-dimensional rosette nanotubes (RNTs) featuring the porphyrin or oligiothiophene groups on the outer surface. Using a combination of imaging and spectroscopic techniques we established the structure of the TPPO-(G∧C)2 and 6T-(G∧C)2 RNTs and compared the HOMO and LUMO energy levels with PC61BM, a well-known electron acceptor material. These studies, in combination with solid-state photoluminescence data of PC61BM-TPPO-(G∧C)2 RNT blended thin films, indicates that these self-assembled nanomaterials have great potential as electron donor materials for solution-processed organic photovoltaics.

scholarly journals Synthesis of Novel Derivatives of Carbazole-Thiophene, Their Electronic Properties, and Computational Studies

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
E. F. Damit ◽  
N. Nordin ◽  
A. Ariffin ◽  
K. Sulaiman
Keyword(s):  
Electronic Properties ◽  
Theoretical Calculations ◽  
Energy Levels ◽  
Phenyl Group ◽  
Cyclic Voltammogram ◽  
Coupling Reactions ◽  
Lumo Energy ◽  
Homo And Lumo ◽  
Derivatives Of ◽  
Homo And Lumo Energy

A series of carbazole-thiophene dimers,P1–P9, were synthesized using Suzuki-Miyaura and Ullmann coupling reactions. InP1–P9, carbazole-thiophenes were linked at the N-9 position for different core groups via biphenyl, dimethylbiphenyl, and phenyl. Electronic properties were evaluated by UV-Vis, cyclic voltammogram, and theoretical calculations. Particularly, the effects of conjugation connectivity on photophysical and electrochemical properties, as well as the correlation between carbazole-thiophene and the core, were studied. Carbazole connecting with thiophenes at the 3,6-positions and the phenyl group as a core group leads to increased stabilization of HOMO and LUMO energy levels where the bandgap (ΔE) is significantly reduced.

scholarly journals Fluorescent Indolo[2,3-b]quinoxalin-2-yl)(Phenyl)methanone Dyes: Photophysical, Aie Activity, Electrochemical, and Theoretical Studies

2021 ◽  
Author(s):  
Deepali Kanekar ◽  
Sudhakar Dhanawade ◽  
Anand Jadhav ◽  
Mohmmed Ghadiyali ◽  
Sajeev Chacko ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Energy Levels ◽  
Potential Candidate ◽  
Good Thermal Stability ◽  
Td Dft ◽  
Solid Film ◽  
Donor Acceptor ◽  
Homo And Lumo ◽  
Photophysical Studies ◽  
Homo And Lumo Energy

Abstract Herein, we have synthesized four indolo[2,3-b]quinoxalin-2-yl)(phenyl)methanone derivatives 1−4 by cyclocondensation. The photophysical studies of dyes in various solvents and neat solid film exhibit typical electronic spectra with inbuilt intramolecular charge transfer (ICT) (λmax: 397‒490 nm) confirming donor-acceptor architecture. Herein, dyes fluoresce in the blue-orange region (λEmax: 435–614) on excitation at their ICT maxima in toluene, ethyl acetate, chloroform, DMSO, and neat solid film. 1 and 2 which exhibit good emission intensity in all mediums, were studied for aggregation-induced emission (AIE) effect. Electrochemical studies indicate 1−4 possess relatively low lying LUMO (‒3.65 to ‒3.98 eV) comparable to reported n-type/electron-transporting materials. The HOMO and LUMO energy levels in 1−4 were evaluated by DFT and TD-DFT calculations. TGA analysis shows 1−4 exhibit good thermal stability. The characteristic optoelectronic properties and thermal stability signify these dyes are potential candidate for their application in optoelectronics.

Absolute Configuration of Scopolamine N-Oxide and of Related Compounds

1971 ◽  
Vol 49 (20) ◽  
pp. 3258-3271 ◽  
Author(s):  
Carol Saunderson Huber ◽  
Gabor Fodor ◽  
Nagabhushanam Mandava
Keyword(s):  
Absolute Configuration ◽  
Chemical Shifts ◽  
Complete Agreement ◽  
Anomalous Scattering ◽  
Product Analysis ◽  
X Ray Crystallography ◽  
Chemical Correlation ◽  
A Minor ◽  
First Time ◽  
Related Compounds

Structure analysis of (−) scopolamine N-oxide (1) hydrobromide monohydrate by X-ray crystallography has proven that the N-methyl group is axial and the amineoxide function is equatorial. The absolute configuration of the tropic acid residue has also been determined by anomalous scattering as being S, in complete agreement with chemical correlation experiments.The N-stereoisomer of 1 has also been detected as a minor product 2 for the first time, as a result of using 100 MHz n.m.r. spectroscopy in the product analysis of the oxidation of (−) scopolamine with hydrogen peroxide in ethanol. A similar n.m.r. study was undertaken with atropine and tropine and correlation of chemical shifts with N-configuration in the N-oxides, 3–6, was attempted. N-oxidation of scopolamine, and by analogy of related tropane bases, has taken a preferentially equatorial course, similar to other quaternization reactions.

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