Magnets interlocked

Mechanical Guard with electrical or magnetic interlock... 

There are trade-offs for magnetic drive and canned pumps versus centrifugal pumps with double-mechanical seals. The former have no seals to leak, but need active interlocks to prevent high temperature for temperature sensitive materials. Similarly, diaphragm pumps, that have... 

Mn(ll)Cu(II) magnets, 43 253 molecular-based magnet, three spin carriers with full interlocked structure, 43 199, 201-204 Ni(II)Cu(II)binuclear and... 

Soft and Hard Molecule-Based Magnets with a Fully Interlocked Three-Dimensional Structure... 

In this contribution, we would like to show how such an approach allowed us to synthesize both soft and very hard molecule-based magnets. This contribution is organized as follows first, we define briefly the field of molecular magnetism, then we indicate the successive steps which led us to three-dimensional molecule-based magnets with fully interlocked structures. We describe these original structures in detail. Finally, we focus on the physical properties of these objects, with special emphasis on the huge coercivity of one of the compounds, which confers a memory effect on this compound. 

Structure of Molecule-Based Magnets Containing Three Spin Carriers, with a Fully Interlocked Structure... 

The magnets described in this work are among the very few two- or three-dimensional molecular structures with complete interlocking of independent infinite networks. Other examples are silver tricyanomethide [17], trimesic acid [18], dia-quabis(4,4 -bipyridine)zinc hexafluorosilicate [19], zinc bis(tricyanomethide) [20], and bis(l,2-di-(4-pyridyl)-ethylene-bis(thiocyanato)iron(H) [21]. Interlocking of rings in discrete supramolecular units is much more developed [22-25] and most of this book is devoted to this topic. 

In a serendipitous fashion, a novel mixed valence tetranuclear copper(II)/copper(III) dithiocarbamate [2]catenane was prepared in near quantitative yield by partial chemical oxidation of a preformed dinuclear copper(II) naphthyl dtc macrocycle (Scheme 6).49 X-ray structure, magnetic susceptibility, ESMS and electrochemical studies all support the tetranuclear catenane dication formulation. The combination of the lability of copper(II) dtc coordinate bonds and favourable copper(II) dtc-copper(III) dtc charge transfer stabilisation effects are responsible for the high yielding formation of the interlocked... 

From a stereochemical analysis of binding anions, the interlocking-sites model is most consistent with available data. We have approached the question of the spatial relationship of metal ion and anion in human transferrin through electron and nuclear magnetic resonance spectroscopy (17,49). 

H Nuclear magnetic resonance (NMR) and UV-Vis spectroscopies were applied to studies on complexation between various TTF donors, among others, TTF 16 and the 7t-electron-accepting tetracationic cyclophane 28 (CBPQT ). The results obtained were of fundamental importance in designing interlocked molecular systems like molecular switches in which CBPQT and TTF units were incorporated <2001JOC3559>. H NMR investigations of similar systems are referred to at the end of this subsection. 

Liquid bridges occur when a liquid is sprayed to wet the surface of the particles, then they colhde with other particles and the hquid connects the particles. Molecular, electrical, or magnetic forces between particles is another binding mechanism. Interlocking occurs when irregular-shaped particles collide and lock together. A matrix binder has particles that are imbedded in a continuous matrix of the binder. 

Outstanding examples of the use of computers in chemistry are in the fields of mass spectrometry, nuclear magnetic resonance, and the many techniques for surface analysis. Developments in these fields have been a matter of slow, but sustained improvement. One reason for the slowness of the developments seems to have been the time needed to introduce the different areas of science which are necessary for a complete system. Foremost amongst these areas is computing science. Computing systems are notoriously difficult and slow to develop because of the complexity and number of the necessary and interlocking software and hardware modules. 

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