Lattice contraction

Au microcrystals supported in gelatin Correlation of isomer shift with lattice contraction... 

Another effect of lattice contraction of a boron-implanted layer might be to cause reorientation of the B—H complexes in the layer. Calculations (Denteneer et al., 1989) and measurements (Stavola et al., 1988) show that the B—H complex can readily reorient itself in response to an applied stress at room temperature. Thus, reorientation might occur in a boron-implanted layer and vitiate the analysis of the channeling experiment. In a (100) sample, however, all the (111) directions lie at the same angle to the stress axis if relaxation in the plane of the sample is isotropic, and all orientations of the B—H complex are energetically equivalent. This would not be true in (111) material. 

In this chapter, hydrogen adsorption, particularly observed on Pt electrodes, was not treated as an underpotential deposition phenomenon. However, from a theoretical point of view, it may provide a breakthrough insight into underpotential deposition. Since the underpotential deposition ofM on M is quite characteristic among different combinations of M and M, together with a change in the kind of anions in the solution, a theoretical approach, which requires simplification, is still limited, and more experimental clarification is needed for theoretical work. However, the jellium model was successfully used to describe the lattice contraction of adsorbate T1 and Pb on Ag(lll) as underpotential deposition. ... 

In many catalytic systems, nanoscopic metallic particles are dispersed on ceramic supports and exhibit different stmctures and properties from bulk due to size effect and metal support interaction etc. For very small metal particles, particle size may influence both geometric and electronic structures. For example, gold particles may undergo a metal-semiconductor transition at the size of about 3.5 nm and become active in CO oxidation [10]. Lattice contractions have been observed in metals such as Pt and Pd, when the particle size is smaller than 2-3 nm [11, 12]. Metal support interaction may have drastic effects on the chemisorptive properties of the metal phase [13-15]. Therefore the stmctural features such as particles size and shape, surface stmcture and configuration of metal-substrate interface are of great importance since these features influence the electronic stmctures and hence the catalytic activities. Particle shapes and size distributions of supported metal catalysts were extensively studied by TEM [16-19]. Surface stmctures such as facets and steps were observed by high-resolution surface profile imaging [20-23]. Metal support interaction and other behaviours under various environments were discussed at atomic scale based on the relevant stmctural information accessible by means of TEM [24-29]. 

In 2008, the A15 or body-centered cubic (bcc) CssCgo phase, which shows bulk superconductivity under applied hydrostatic pressure, was obtained, together with a small amount of by-products of body-centered orthorhombic (bco) and fee phases, by a solution process in liquid methylamine (Prassides, Rosseinsky, et al.) [312]. Interestingly, the lattice contraction with respect to pressure results in an increase in Tc up to around 0.8 GPa, above which Tc gradually decreases. The highest Tc is... 

This means that as the expanded lattice is contracted in the thought experiment, the discrete energy states of the atoms are replaced by energy bands. Thus, when the lattice-contraction thought experiment is finally halted with atoms at their equilibrium interatomic distances, the electron-energy states show a band structure. 

The presence of phase transitions at 19 and 30°C provides an opportunity to test the proposed deformation model. Below 19°C the lattice contracts into a triclinic structure witli strong intermolecular interaction. 5,26 sjamplcs deformed below 19°C should develop off-c-axis orientation while samples deformed above 30°C should not. Figures 1.12 and 1.13 show inverse pole figures for samples deformed at 2 and 70°C. The observed orientation agrees with our proposed model. - With tlris set of experiments, it is possible to activate the oblique slip process or, alternatively, to deactivate it in the high-temperature phase above 30°C. 

Normally the second-order crossover is completed in a pressure span 50 kB. In the case of SmS the first-order transition coming at 6 — 1/2 kB (at 300 K) precipitates the compound almost from the onset of crossover to a stage (as gauged from the observed lattice contraction) approximately 3/4 of the way through the ICF state. Possibly 30 kB more brings a completion of crossover (5), and a termination of the (ICF) anomalous electromagnetic properties (see App 4). 

Ehrlich, H.P., G.M. Allison, M.J. Page, W.A. Kolton, and M. Graham. 2000. Increased gelsolin expression and retarded collagen lattice contraction with smooth muscle cells from Crohn s diseased intestine. J Cell Physiol. 182 303-9. 

Substrate effects may have an important influence on the lattice parameter of small particles. There are several reports of lattice contraction,142-144 but... 

A simple quantitative model, with no adjustable parameters, is developed for the finite size effect of ferroelectric particles on the Curie transition temperature. As the size of ferroelectric particles decreases, the Curie temperature decreases. Based on our model for lattice contraction and the Landau-Ginsburg-Devonshire (LGD) phenomenological theory, size effects on Curie temperature of lead zirconate titanate PbZri. Ti Oj (PZT, x > 0.6) are considered. It is shown that Curie temperature of PZT (x > 0,6) decreases with decreasing particle size. The predictions of our equation are in agreement with the experimental results. 

It is well known that nanocrystals with free surfaces have considerable lattice contraction induced by the large surface/volume ratio. The lattice contraction increases as the size of the nanocrystals decreases. In this contribution, we have considered the size-dependence of the Curie temperature of PZT induced by lattice contraction when the particles size goes into nanometer range. Useful results have been obtained. However, we have neglected the extrinsic contributions on properties, which are caused by domain wall, defect motion, and/or surface charge, etc. The extrinsic properties are more or less affected by the materials processing technology and discussion of them is out of the scope of the present study. 

Cells based on this process (Eq. (47)) show lower cycling performance with respect to those based on the 4 V process because charge-discharge reactions are accompanied by an asymmetric lattice contraction-expansion of the Lii+.vMn204 electrode. This lattice distortion mainly results from the Jahn-Teller effect of the Mn + ion which transforms the crystal symmetry of the spinel oxide [118],... 

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