Mechanochemical synthesis of mechanical bonds in M12L8 poly-[n]-catenanes.

2021 ◽  
Author(s):  
Javier Marti-Rujas ◽  
Stefano Elli ◽  
Alessandro Sacchetti ◽  
Franca Castiglione
Keyword(s):  
Mechanochemical Synthesis ◽  
Mechanical Bond ◽  
Mechanical Bonds

Using mechanochemistry by grinding TPB and ZnBr2 an amorphous poly-[n]-catenane of interlocked M12L8 nanocages is obtained in good yields (⁓ 80 %) and within 15 minutes. The mechanical bond among...

scholarly journals Mechanostereochemistry and the mechanical bond

2012 ◽  
Vol 468 (2146) ◽  
pp. 2849-2880 ◽  
Author(s):  
Gokhan Barin ◽  
Ross S. Forgan ◽  
J. Fraser Stoddart
Keyword(s):  
Self Assembly ◽  
Rapid Development ◽  
Synthetic Methods ◽  
Interlocked Molecules ◽  
Fair Game ◽  
Mechanical Bond ◽  
Covalently Linked ◽  
Mechanical Bonds ◽  
Molecular Compounds ◽  
Knots And Links

The chemistry of mechanically interlocked molecules (MIMs), in which two or more covalently linked components are held together by mechanical bonds , has led to the coining of the term mechanostereochemistry to describe a new field of chemistry that embraces many aspects of MIMs, including their syntheses, properties, topologies where relevant and functions where operative. During the rapid development and emergence of the field, the synthesis of MIMs has witnessed the forsaking of the early and grossly inefficient statistical approaches for template-directed protocols, aided and abetted by molecular recognition processes and the tenets of self-assembly. The resounding success of these synthetic protocols, based on templation, has facilitated the design and construction of artificial molecular switches and machines, resulting more and more in the creation of integrated functional systems. This review highlights (i) the range of template-directed synthetic methods being used currently in the preparation of MIMs; (ii) the syntheses of topologically complex knots and links in the form of stable molecular compounds; and (iii) the incorporation of bistable MIMs into many different device settings associated with surfaces, nanoparticles and solid-state materials in response to the needs of particular applications that are perceived to be fair game for mechanostereochemistry.

Mechanostereochemistry

2010 ◽  
Vol 82 (8) ◽  
pp. 1569-1574 ◽  
Author(s):  
Mark A. Olson ◽  
Youssry Y. Botros ◽  
J. Fraser Stoddart
Keyword(s):  
Mechanical Bond ◽  
Mechanical Bonds ◽  
Noncovalent Bonding ◽  
Configuration And Conformation

Stereochemistry—in both its static and dynamic variants—has progressed apace now for more than a century to incorporate all aspects of covalent, coordinative, and noncovalent bonding at levels of structure which encompass constitution, configuration, and conformation. The advent of the mechanical bond in more recent times is now providing opportunities for the emergence of new stereochemical tenets and concepts, some of which bear close analogies with those of days gone by in chemistry. Since terminology helps to define and disseminate a discipline, we advocate that the term “mechanostereochemistry” be used to describe the chemistry of molecules with mechanical bonds.

Under Pressure: Mechanochemical Effects on Structure and Ion Conduction in the Sodium-Ion Solid Electrolyte Na3PS4

2020 ◽  
Author(s):  
Theodosios Famprikis ◽  
O. Ulas Kudu ◽  
James Dawson ◽  
Pieremanuele Canepa ◽  
François Fauth ◽  
...  
Keyword(s):  
Ionic Conductivity ◽  
Mechanochemical Synthesis ◽  
Activation Volume ◽  
External Pressure ◽  
Sodium Ion ◽  
Variable Pressure ◽  
Ion Conductor ◽  
Ceramic Synthesis ◽  
Solid State Batteries ◽  
Fast Ion

<div> <p>Fast-ion conductors are critical to the development of solid-state batteries. The effects of mechanochemical synthesis that lead to increased ionic conductivity in an archetypical sodium-ion conductor Na<sub>3</sub>PS<sub>4</sub> are not fully understood. We present here a comprehensive analysis based on diffraction (Bragg, pair distribution function), spectroscopy (impedance, Raman, NMR, INS) and <i>ab-initio</i> simulations aimed at elucidating the synthesis-property relationships in Na<sub>3</sub>PS<sub>4</sub>. We consolidate previously reported interpretations about the local structure of ball-milled samples, underlining the sodium disorder and showing that a local tetragonal framework more accurately describes the structure than the originally proposed cubic one. Through variable-pressure impedance spectroscopy measurements, we report for the first time the activation volume for Na<sup>+</sup> migration in Na<sub>3</sub>PS<sub>4</sub>, which is ~30% higher for the ball-milled samples. Moreover, we show that the effect of ball-milling on increasing the ionic conductivity of Na<sub>3</sub>PS<sub>4</sub> to ~10<sup>-4</sup> S/cm can be reproduced by applying external pressure on a sample from conventional high temperature ceramic synthesis. We conclude that the key effects of mechanochemical synthesis on the properties of solid electrolytes can be analyzed and understood in terms of pressure, strain and activation volume.</p> </div>

Theoretical and Experimental Evaluation of the Effect of Fluorinated Substituent on the Topological Landscape and Thermodynamic Stability of Zeolitic Imidazolate Framework Polymorphs

2018 ◽  
Author(s):  
Mihails Arhangelskis ◽  
Athanassis Katsenis ◽  
Novendra Novendra ◽  
Zamirbek Akimbekov ◽  
Dayaker Gandrath ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Mechanochemical Synthesis ◽  
Thermodynamic Stability ◽  
Experimental Evaluation ◽  
Density Functional ◽  
Theoretical Calculations ◽  
Zeolitic Imidazolate Framework ◽  
Functional Theory ◽  
Calorimetric Measurements ◽  
And Calorimetry

By combining mechanochemical synthesis and calorimetry with theoretical calculations, we demonstrate that dispersion-corrected periodic density functional theory (DFT) can accurately survey the topological landscape and predict relative energies of polymorphs for a previously inaccessible fluorine-substituted zeolitic imidazolate framework (ZIF). Experimental screening confirmed two out of three theoretically anticipated polymorphs, and the calorimetric measurements provided an excellent match to theoretically calculated energetic difference between them.<br>

Fast Mechanochemical Synthesis of Nano-structured PMN at Low Temperature

2010 ◽  
Vol 25 (5) ◽  
pp. 541-545 ◽  
Author(s):  
Hao WU ◽  
Cheng CHEN ◽  
Dan-Yu JIANG ◽  
Qiang LI
Keyword(s):  
Low Temperature ◽  
Mechanochemical Synthesis

Comparative Study of Acid Etching on Dental Enamel

2018 ◽  
Vol 69 (10) ◽  
pp. 2913-2915
Author(s):  
Daniela Jumanca ◽  
Anamaria Matichescu ◽  
Atena Galuscan ◽  
Laura Cristina Rusu ◽  
Cornelia Muntean
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Experimental Study ◽  
Orthophosphoric Acid ◽  
Dental Enamel ◽  
Acid Etching ◽  
Sealing Material ◽  
Mechanical Bond ◽  
Materials Used ◽  
Scanning Electron

This experimental study aims to analyse the effectiveness of various materials used in demineralisation of dental enamel. This work aims to create a mechanical bond by filling the pegs with sealing material. In order to achieve this goal, five teeth were compared using different concentrations of orthophosphoric acid and exposure times. In this regard, five different tests were performed and the results were analysed using the SEM technique (scanning electron microscopy). These comparative analyses revealed that etching using 35% orthophosphoric acid for one minute and etching using Icon Etch for two minutes were the most effective.

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