scholarly journals Structure–property relationships and third-order nonlinearities in diketopyrrolopyrrole based D–π–A–π–D molecules

2017 ◽  
Vol 13 ◽  
pp. 2374-2384 ◽  
Author(s):  
Jan Podlesný ◽  
Lenka Dokládalová ◽  
Oldřich Pytela ◽  
Adam Urbanec ◽  
Milan Klikar ◽  
...  
Keyword(s):  
Emission Spectra ◽  
Coupling Reactions ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Third Order ◽  
Third Harmonic ◽  
Fundamental Properties ◽  
Cross Coupling Reactions ◽  
Structure Property Relationships ◽  
Target Molecules

Nine new quadrupolar chromophores based on diketopyrrolopyrrole were designed and prepared by cross-coupling reactions. The property tuning has been achieved by structural variation of the peripheral substituents (donor) and enlargement of the π-system. Fundamental properties of target molecules were studied by differential scanning calorimetry, electrochemistry, and absorption and emission spectra. Nonlinear optical properties were studied by measuring the third harmonic generation. The experimental data were completed by quantum-chemical calculations and structure–property relationships were elucidated.

scholarly journals Synthesis, photophysical and electrochemical characterization of terpyridine-functionalized dendritic oligothiophenes and their Ru(II) complexes

2013 ◽  
Vol 9 ◽  
pp. 866-876 ◽  
Author(s):  
Amaresh Mishra ◽  
Elena Mena-Osteritz ◽  
Peter Bäuerle
Keyword(s):  
Density Functional ◽  
Dendritic Structure ◽  
Spectroscopic Properties ◽  
Coupling Reactions ◽  
Structure Property ◽  
Cross Coupling Reactions ◽  
Structure Property Relationships ◽  
Maldi Tof Mass Spectra ◽  
New Compounds

Pd-catalyzed Sonogashira cross-coupling reactions were used to synthesize novel π-conjugated oligothienylene-ethynylene dendrons and their corresponding terpyridine-based ligands. Their complexation with Ru(II) led to interesting novel metallodendrimers with rich spectroscopic properties. All new compounds were fully characterized by 1H and 13C NMR, as well as MALDI–TOF mass spectra. Density functional theory (DFT) calculations performed on these complexes gave more insight into the molecular orbital distributions. Photophysical and electrochemical studies were carried out in order to elucidate structure–property relationships and the effect of the dendritic structure on the metal complexes. Photophysical studies of the complexes revealed broad absorption spectra covering from 250 to 600 nm and high molar extinction coefficients. The MLCT emission of these complexes were significantly red-shifted (up to 115 nm) compared to the parent [Ru(tpy)2]2+ complex.

Nonresonant Third-Order Nonlinear Polarizability in Linear Conjugated Molecules

1987 ◽  
Vol 109 ◽  
Author(s):  
S. H. Stevenson ◽  
D. S. Donald ◽  
G. R. Meredith
Keyword(s):  
Structure Property ◽  
Third Order ◽  
Conjugated Molecules ◽  
Third Harmonic ◽  
Molecular Features ◽  
Structure Property Relationships ◽  
Liquid Solutions ◽  
Optical Applications ◽  
Nonlinear Optical Applications ◽  
Nonlinear Polarizability

ABSTRACTCrude pictures relating molecular features and enhancement of nonresonant second-order hyperpolarizability have been known and successfully utilized in selection and preparation of materials for nonlinear-optical applications for over a decade. On the other hand, other than the requirement of “electron delocalization”, such a useful picture does not exist for nonresonant third-order hyperpolarizability. In pursuit of such a picture, and to obtain a better view of the range of hyperpolarizability magnitudes which might be obtainable, simple linear conjugated molecules have been synthesized and characterized. Liquid solutions of these model compounds were studied using recently developed high precision optical third harmonic generation techniques. Results of these characterizations and a new addition to the picture of structure-property relationships are reported.

meso-Expanded Co(III)corroles through Suzuki-Miyaura couplings: Synthesis and tunable electrocatalytic hydrogen evolutions and oxygen reductions

2021 ◽  
pp. A-I
Author(s):  
Xifeng Zhang ◽  
Wenwu Guo ◽  
Weihua Zhu ◽  
Xu Liang
Keyword(s):  
Electronic Structure ◽  
Hydrogen Evolution ◽  
Structural Characterization ◽  
Coupling Reactions ◽  
Structure Property ◽  
Electrochemical Catalysis ◽  
Oxygen Reduction Reactions ◽  
Structure Property Relationships ◽  
Hydrogen Evolution Reactions ◽  
Positional Isomerism

In this study, four meso-expanded Co(III)corroles at meta-positions through Suzuki–Miyaura coupling reactions and their structural characterization are successfully accomplished and reported. An analysis of the structure–property relationships by spectroscopy, electrochemistry and electrochemical catalysis demonstrate how the positional isomerism influence the electronic structure and their catalytic behaviors of hydrogen evolution reactions (HERs) and oxygen reduction reactions (ORRs).

Synthesis and Liquid Crystalline Properties of New Chiral Monomers and Polysiloxanes

2013 ◽  
Vol 815 ◽  
pp. 747-751
Author(s):  
Jian She Hu ◽  
Yi Nan Liu ◽  
Ya Ting Song ◽  
Di Wang
Keyword(s):  
Liquid Crystalline ◽  
Structure Property ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Cholesteric Phase ◽  
Crystalline Materials ◽  
H Nmr ◽  
Structure Property Relationships ◽  
Potential Applications ◽  
Liquid Crystalline Materials

To study the structure-property relationships of new chiral liquid crystalline materials based on menthol and explore their potential applications, a monomer 4-(4-allyloxybenzoyloxy) phenyl-4-menthyl-oxyacetyloxybiphenyl-4-carboxylate (LCM) and the corresponding homopolymer (LCP) were synthesized. The chemical structure was characterized by FT-IR and 1H NMR. The liquid crystalline properties were investigated by differential scanning calorimetry, thermogravimetric analysis, polarizing optical microscopy, and X-ray diffraction. The monomer LCM formed a cholesteric phase when a flexible linkage chain was inserted between the mesogenic core and the terminal menthyl groups by reducing the steric effect. The homopolymer LCP exhibited a batonnet texture of a smectic A phase.

scholarly journals Characterization of Composition and Structure–Property Relationships of Commercial Post-Consumer Polyethylene and Polypropylene Recyclates

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1574
Author(s):  
Markus Gall ◽  
Paul J. Freudenthaler ◽  
Joerg Fischer ◽  
Reinhold W. Lang
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Charpy Impact ◽  
Impact Testing ◽  
Gravimetric Analysis ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Melt Flow Rate ◽  
Impact Performance ◽  
Structure Property Relationships ◽  
Composition And Structure

The current efforts in moving closer towards a circular plastics economy puts massive pressure on recycled plastics, especially recycled polyethylene (rPE) and recycled polypropylene (rPP) to enter new markets. Their market penetration remained low so far, despite PE and PP constituting the largest share of plastic wastes. However, with the current imperative of more circularity comes a new focus on performance of recyclates. Hence, a detailed understanding of composition and structure–property relationships of post-consumer recyclates has to be developed. Five recycling companies from the Austrian and German markets were asked to supply their purest high-quality rPE and rPP grades. These were characterized by differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), and Fourier-transform infrared (FTIR) spectroscopy, and micro-imaging. Technological characterization included density measurements, determination of the melt flow rate (MFR), and Charpy impact testing. All recyclates contained diverse contaminants and inclusions ranging from legacy fillers like calcium carbonate to polymeric contaminants like polyamides or polyolefin cross-contamination. The overall amount, size, and distribution of contaminants varied significantly among suppliers. Furthermore, first structure–property relationships for polyolefin recyclates that link inorganic content and polymeric purity with density and impact performance could be derived.

Thermal and Spectral Analysis of Novel Amide-Tethered Polymers from Poly(allylamine)

2016 ◽  
Vol 69 (4) ◽  
pp. 458
Author(s):  
Paolo N. Grenga ◽  
Matthew J. Nethercott ◽  
Ayeisca E. Mateo ◽  
Mathew Patenaude ◽  
Todd Hoare ◽  
...  
Keyword(s):  
Solid State Nmr ◽  
Differential Scanning Calorimetry Analysis ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Multilayer Systems ◽  
Amide Linkage ◽  
Structure Property Relationships ◽  
Modified Polymers ◽  
Tethered Polymers ◽  
Allylamine Hydrochloride

Post-polymerization modification of poly(allylamine hydrochloride) was applied to synthesize a library of amide-linked polyelectrolytes with tethered aliphatic, aromatic, and cubyl moieties. The efficacy of amidation was determined to be between 12 and 98 %, depending on the electronics, sterics, and solubility of the amide linkage. 13C solid-state NMR was used to further validate their structure. Thermogravimetric analysis and differential scanning calorimetry analysis indicated that none of the new polymers displayed a classic melt/freeze profile, but all displayed onset decomposition temperatures smaller than 215°C. We anticipate that the structure–property relationships observed in the resulting library of graft-modified polymers can facilitate better understanding of how to design polyelectrolytes for the construction of well-defined multilayer systems.

scholarly journals Significance of Theoretical Decomposition Enthalpies for Predicting Thermal Hazards

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Didier Mathieu
Keyword(s):  
Differential Scanning Calorimetry ◽  
Nitroaromatic Compounds ◽  
Present Approach ◽  
Quantitative Structure ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Thermal Hazards ◽  
Structure Property Relationships ◽  
Quantitative Structure Property Relationships ◽  
Decomposition Enthalpy

Much effort is currently put into the development of models for predicting decomposition enthalpies measured using differential scanning calorimetry (DSC). As an alternative to the purely empirical schemes reported so far, this work relies on theoretical values obtained on the basis of simple assumptions. For nitroaromatic compounds (NACs) studied in sealed sample cells, our approach proves clearly superior to previous ones. In contrast, it correlates poorly with data measured in pin-hole sample cells. Progress might be obtained through a combination of the present approach with the usual Quantitative Structure-Property Relationships (QSPR) methodologies. This work emphasizes the significance of the theoretical decomposition enthalpy as a fundamental descriptor for the prediction of DSC values. In fact, the theoretical value provides a valuable criterion to characterize thermal hazards, as a complement to experimental decomposition temperatures.

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