scholarly journals Elastic Organic Crystals of π-Conjugated Molecules: New Concept for Materials Chemistry

Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2022
Author(s):  
Shotaro Hayashi
Keyword(s):  
Small Molecules ◽  
Single Crystals ◽  
State Of The Art ◽  
Functional Materials ◽  
Molecular Structures ◽  
Organic Crystal ◽  
Organic Crystals ◽  
Materials Chemistry ◽  
Conjugated Molecules ◽  
Recent Emergence

It is generally believed that organic single crystals composed of a densely packed arrangement of anisotropic, organic small molecules are less useful as functional materials due to their mechanically inflexible and brittle nature, compared to polymers bearing flexible chains and thereby exhibiting viscoelasticity. Nevertheless, organic crystals have attracted much attention because of their tunable optoelectronic properties and a variety of elegant crystal habits and unique ordered or disordered molecular packings arising from the anisotropic molecular structures. However, the recent emergence of flexible organic crystal materials showing plasticity and elasticity has considerably changed the concept of organic single crystals. In this review, the author summarizes the state-of-the-art development of flexible organic crystal materials, especially functional elastic organic crystals which are expected to provide a foothold for the next generation of organic crystal materials.

Curving deformation-induced photoluminescence changes and anisotropy analysis in elastic organic crystals

CrystEngComm ◽  
2021 ◽  
Author(s):  
Shotaro Hayashi
Keyword(s):  
Physical Properties ◽  
Molecular Crystals ◽  
Mechanical Deformation ◽  
Organic Crystal ◽  
Organic Crystals ◽  
Materials Chemistry

Mechanical deformation-induced physical properties changes of flexible molecular crystals are unique topics in materials chemistry. Here, the mechanically curving-induced photoluminescence (PL) and PL anisotropy changes in an elastic organic crystal...

Visualizing 3D Molecular Structures Using an Augmented Reality App

2019 ◽  
Author(s):  
Kristina Eriksen ◽  
Bjarne Nielsen ◽  
Michael Pittelkow
Keyword(s):  
Augmented Reality ◽  
Small Molecules ◽  
Computer Modelling ◽  
Simple Procedure ◽  
3D Structure ◽  
Molecular Structures ◽  
Free Software ◽  
Programming Skills ◽  
2D Space ◽  
Made In

<p>We present a simple procedure to make an augmented reality app to visualize any 3D chemical model. The molecular structure may be based on data from crystallographic data or from computer modelling. This guide is made in such a way, that no programming skills are needed and the procedure uses free software and is a way to visualize 3D structures that are normally difficult to comprehend in the 2D space of paper. The process can be applied to make 3D representation of any 2D object, and we envisage the app to be useful when visualizing simple stereochemical problems, when presenting a complex 3D structure on a poster presentation or even in audio-visual presentations. The method works for all molecules including small molecules, supramolecular structures, MOFs and biomacromolecules.</p>

Cholesterol decorated pyridinium urea and carbamate as π-gelators for selective recognition of F- ions

2021 ◽  
Vol 05 ◽  
Author(s):  
Santanu Panja ◽  
Kumaresh Ghosh
Keyword(s):  
Sol Gel ◽  
Functional Materials ◽  
Materials Chemistry ◽  
Eye Detection ◽  
Fluoride Ions ◽  
Biologically Relevant ◽  
Design And Synthesis ◽  
Naked Eye ◽  
Visual Sensing ◽  
Naked Eye Detection

Aim: Design and synthesis of new molecules capable of forming self-assembled gels are indispensable to harvest new functional materials. Supramolecular gels have potential in many areas particularly in biology and materials chemistry. Of the different types of applications, visual sensing of biologically relevant ionic analytes is a fairly recent trend. Here we describe naked eye detection of fluoride ions involving sol-gel methodology. Methods: To execute this, cholesterol substituted pyridinium salts 1-4 have been designed and synthesized of which compounds 3 and 4 served as potential gelators for the naked eye detection of F- ions in DMSO and DMSO-H2O (1:1, v/v) respectively. Results: Gelation study reveals that not only the aromatic surface is crucial for the self-aggregation of molecules via π-π stacking interactions, but also polarity, rigidity and conformational flexibility of the molecules that govern the intermolecular association of gelators are important. Conclusion: Moreover, incorporation of fluorophores (naphthalene) as aromatic surface in the molecular designs, promotes the gelator molecules to execute sensing behavior for F- with high degree of sensitivity in solution phase also.

Photorearrangement of 2-cyanobicyclo[2.2.1]hept-2-ene. Observation of 1,2- and 1,3-sigmatropic shifts

1982 ◽  
Vol 60 (13) ◽  
pp. 1657-1663 ◽  
Author(s):  
Ikbal A. Akhtar ◽  
John J. McCullough ◽  
Susan Vaitekunas ◽  
Romolo Faggiani ◽  
Colin J. L. Lock
Keyword(s):  
Single Crystals ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Major Product ◽  
Molecular Structures ◽  
Lithium Aluminum ◽  
Mercury Vapour ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Mercury Vapour Lamp

Irradiation of 2-cyanobicyclo[2.2.1]hept-2-ene (2-cyanonorbornene, 4) in hexane, with the full arc of a mercury vapour lamp, gives the rearrangement products 1-cyanobicyclo[4.1.0]hept-2-ene 5 and 7-cyanotricyclo[4.1.0.03.7]heptane 6 in the ratio 20:1. These products were separated by preparative vpc. The structure of the major product 5 was determined by single crystal X-ray analysis. Reduction of 5 with lithium aluminum hydride gave the corresponding primary amine, which was converted to the p-bromobenzenesulfonamide 9, mp 150–151 °C, which gave single crystals from ethanol–water. The crystal and molecular structures are described. The minor product 6 was hydrogenated to give 7-cyanobicyclo[2.2. 1]heptane. Formation of 5 and 6 may involve concerted σ2s + π2s and σ2a + π2a processes respectively, which are photochemically allowed.

scholarly journals Plant Antimicrobial Peptides: State of the Art, In Silico Prediction and Perspectives in the Omics Era

2020 ◽  
Vol 14 ◽  
pp. 117793222095273 ◽  
Author(s):  
Carlos André dos Santos-Silva ◽  
Luisa Zupin ◽  
Marx Oliveira-Lima ◽  
Lívia Maria Batista Vilela ◽  
João Pacifico Bezerra-Neto ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Small Molecules ◽  
In Silico ◽  
State Of The Art ◽  
Environmental Stresses ◽  
Gene Duplications ◽  
In Silico Prediction ◽  
Sequence Alignments ◽  
Plant Families ◽  
Simple Sequence

Even before the perception or interaction with pathogens, plants rely on constitutively guardian molecules, often specific to tissue or stage, with further expression after contact with the pathogen. These guardians include small molecules as antimicrobial peptides (AMPs), generally cysteine-rich, functioning to prevent pathogen establishment. Some of these AMPs are shared among eukaryotes (eg, defensins and cyclotides), others are plant specific (eg, snakins), while some are specific to certain plant families (such as heveins). When compared with other organisms, plants tend to present a higher amount of AMP isoforms due to gene duplications or polyploidy, an occurrence possibly also associated with the sessile habit of plants, which prevents them from evading biotic and environmental stresses. Therefore, plants arise as a rich resource for new AMPs. As these molecules are difficult to retrieve from databases using simple sequence alignments, a description of their characteristics and in silico (bioinformatics) approaches used to retrieve them is provided, considering resources and databases available. The possibilities and applications based on tools versus database approaches are considerable and have been so far underestimated.

scholarly journals Boron(iii) β-diketonate-based small molecules for functional non-fullerene polymer solar cells and organic resistive memory devices

2020 ◽  
Vol 11 (42) ◽  
pp. 11601-11612
Author(s):  
Panpan Li ◽  
Quanbin Liang ◽  
Eugene Yau-Hin Hong ◽  
Chin-Yiu Chan ◽  
Yat-Hin Cheng ◽  
...  
Keyword(s):  
Solar Cells ◽  
Small Molecules ◽  
Polymer Solar Cells ◽  
Functional Materials ◽  
Memory Devices ◽  
Resistive Memory

Boron(iii) β-diketonates have been demonstrated to serve as multi-functional materials in NFA-based OPVs and organic resistive memories.

scholarly journals The hetero-Friedel-Crafts-Bradsher Cyclizations with Formation of Ring Carbon-Heteroatom (P, S) Bonds, Leading to Organic Functional Materials

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4751
Author(s):  
Joanna Skalik ◽  
Marek Koprowski ◽  
Ewa Różycka-Sokołowska ◽  
Piotr Bałczewski
Keyword(s):  
Flame Retardants ◽  
Bond Formation ◽  
Functional Materials ◽  
Semiconducting Materials ◽  
Conjugated Molecules ◽  
Comprehensive Review ◽  
Ring Carbon ◽  
New Methods ◽  
Cyclic Molecules ◽  
Methods Of Synthesis

The interest in functional materials possessing improved properties led to development of new methods of their synthesis, which allowed to obtain new molecular arrangements with carbon and heteroatom motifs. Two of the classical reactions of versatile use are the Friedel-Crafts and the Bradsher reactions, which in the new heteroatomic versions allow to replace ring carbon atoms by heteroatoms. In the present work, we review methods of synthesis of C–S and C–P bonds utilizing thia- and phospha-Friedel-Crafts-Bradsher cyclizations. Single examples of C–As and lack of C–Se bond formation, involving two of the closest neighbors of P and S in the periodic table, have also been noted. Applications of the obtained π-conjugated molecules, mainly as semiconducting materials, flame retardants, and resins hardeners, designed on the basis of five- and six-membered cyclic molecules containing ring phosphorus and sulfur atoms, are also included. This comprehensive review covers literature up to August 2020.

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