Molecular periodicity

Luty, B.A., Davis, M.E., Tironi, I.G., Van Gunsteren, W.F. A comparison of particle-particle particle-mesh and Ewald methods for calculating interactions in periodic molecular systems. Mol. Simul. 14 (1994) 11-20. 

Luty B A, M E David, I G Tironi and W F van Gunsteren 1994. A Comparison of Particle-Particle, Particle-Mesh and Ewald Methods for Calculating Electrostatics Interactions in Periodic Molecular Systems. Molecular Simulation 14 11-20. 

In the past, when molecular mechanics methods were used for transition metals, it was by having a set of parameters for the metal that were parameterized specifically for one class of compounds. There have been a number of full periodic table force fields created, with the most successful being the UFF force field. All the full periodic molecular mechanics methods still give completely unreasonable results for certain classes of compounds. 

Professor R. M. Barrer of Imperial College, London, expressed the opinion that periodic molecular sieve conferences would be worthwhile. On the premise that it was appropriate to hold the first conference in London to honor Professor Barrer s contributions, a group of British scientists was encouraged to initiate its organization. As a result, the first International Conference on Molecular Sieves was held successfully in London, April 4-6, 1967, under the chairmanship of Professor Barrer and under the sponsorship of the Society of Chemical Industry. The conference was attended by some 200 scientists, and 34 papers were presented. The proceedings, Molecular Sieves, is published by the Society of Chemical Industry, 14 Belgrave Square, London, S.W. 1, 1968. 

As described above, the Talbot-Lau interferometer is essentially a lens-less imaging device which produces a strictly periodic molecular density pattern... 

Paria, B.C., Deutsch, D.D., and Dey, S.K. (1996) The uterus is a potential site for anandamide synthesis and hydrolysis differential profiles of anandamide synthase and hydrolase activities in the mouse uterus during the periimplantation period, Molecular Reproduction and Development 45 183-192. 

Polymers differ not only in the composition of their constituents and in the way their structural elements are linked, but also in their molecular architecture. Noteworthy is the enormous influence of periodic molecular arrangements on polymer properties when specific structural units are used and their linkage is defect-free. 

So, while traditionally crystal engineering had its birth in the topochemistry of SchmidtJ or even the earlier ideas on control of crystal packing presented by Pepinsky in 1955, the modem discipline is simply supramolecular chemistry applied to periodic molecular solids. The aim is the rational design of interesting or... 

Nichols, J. W., S. G. Moore, and D. R. Wheeler. 2009. Improved implementation of Kirkwood-Buff solution theory in periodic molecular simulations. Physical Review E. 80, 051203. 

It is a special layer formation susceptibility close to the phase transition the nematic is very sensitive to the spatially periodic molecular field, which induce the density wave with period 1. In order to study this phenomenon one is tempted to use an external spatially periodic force with the same period, but, at present, it is technically impossible. Therefore, we cannot find the Landau coefficient a above T va using some analogy with the Kerr or Cotton-Mouton effects. 

Since (I-A) is a measure of hardness according to the maximum hardness principle, the stability of a system or the favorable direction of a physicochemical process is often dictated by this quantity. Because aromatic systems are much less reactive, especially toward addition reactions, I -A may be considered to be a proper diagnostic of aromaticity. Moreover, (/ - A) has been used in different other contexts, such as stability of magic clusters, chemical periodicity, molecular vibrations and internal rotations, chemical reactions, electronic excitations, confinement, solvation, dynamics in the presence of external field, atomic and molecular collisions, toxicity and biological activity, chaotic ionization, and Woodward-Hoffmann rules. The concept of absolute hardness as a unifying concept for identifying shells and subshells in nuclei, atoms, molecules, and metallic clusters has also been discussed by Parr and Zhou. ... 

We achieved autonomous viscosity oscillation by reversible complex formation of terpyridine-terminated PEG and/or terpyridine-terminated tetra PEG in the BZ reaction [26]. Then the BZ reaction induces the periodical binding/dissociation of the Ru-terpyridine complex and causes periodic molecular changes and results in viscosity changes (Fig. 11.7). Differently from the viscosity oscillation we reported before, this mechanism based on complex formation may be advantageous in terms of... 

RGURE 6 Polyethylene thin-film topography with STM, 6.5 x 9.4 nm, = -67 mV, /, = 1.2 nA, showing the periodic molecular structure of the polyethylene at the surface. 

As shown earlier the conductivity properties are strongly related to the structural classification, which has been already presented. It appears nevertheless that we are not always in the presence of ideal tri-periodic molecular systems but with different kinds of disorders. The influence of these disorders is a rather complicated effect. It depends roughly on two parameters, which are the electronic dimensionality and the nature of the local perturbation. As pointed out in Section 4.1, in pure ID systems any disorder will induce an electronic localization. It appears therefore that this effect will be efficient in disordered ID conductors but weaker in q-2D ones (see Figure 3.12 for a topological classification). 

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