Crystals lattices

In crystals of polyglutamic acid esters, motions of the a-helical regions such as torsion, coaxial vibration, and bending can contribute to mechanical loss, as discussed by Kajiyama, Kuroishi, and Takayanagi.  

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Burger s vector A measure of the crystal lattice displacement resulting from the passage of a dislocation. 

The sensitive layer of the systems under investigation eonsists of a mixture of BaFBr with Eu dotation. Other systems are available in the mean time too. X-ray- or y-quants initiate transitions of electrons in the crystal lattice. Electrons are excited from the valence band to the conduction band [2]. Electrons from the conduction band are trapped in empty Br -lattice places. They can return to the valence band via the conduction band after an excitation by... 

The linear dependence of C witii temperahire agrees well with experiment, but the pre-factor can differ by a factor of two or more from the free electron value. The origin of the difference is thought to arise from several factors the electrons are not tndy free, they interact with each other and with the crystal lattice, and the dynamical behaviour the electrons interacting witii the lattice results in an effective mass which differs from the free electron mass. For example, as the electron moves tlirough tiie lattice, the lattice can distort and exert a dragging force. 

Electrons interact with solid surfaces by elastic and inelastic scattering, and these interactions are employed in electron spectroscopy. For example, electrons that elastically scatter will diffract from a single-crystal lattice. The diffraction pattern can be used as a means of stnictural detenuination, as in FEED. Electrons scatter inelastically by inducing electronic and vibrational excitations in the surface region. These losses fonu the basis of electron energy loss spectroscopy (EELS). An incident electron can also knock out an iimer-shell, or core, electron from an atom in the solid that will, in turn, initiate an Auger process. Electrons can also be used to induce stimulated desorption, as described in section Al.7.5.6. 

Born M and Huang K 1954 Dynamical Theory of Crystal Lattices (Oxford Clarendon)... 

No system is exactly unifomi even a crystal lattice will have fluctuations in density, and even the Ising model must pemiit fluctuations in the configuration of spins around a given spin. Moreover, even the classical treatment allows for fluctuations the statistical mechanics of the grand canonical ensemble yields an exact relation between the isothemial compressibility K j,and the number of molecules Ain volume V ... 

M. Born and K. Huang, Dyncunical Theory of Crystal Lattices, Oxford University Press, New York, 1954. 

The salt-like carbides. Among these are aluminium tricarbide imethanide) AI4C3 (containing essentially C ions) in the crystal lattice and the rather more common dicarbides containing the C ion, for example calcium dicarbide CaCjt these carbides are hydrolysed by water yielding methane and ethyne respectively ... 

Zincill) chloride. ZnCl2, is the only important halide—it is prepared by standard methods, but cannot be obtained directly by heating the hydrated salt. It has a crystal lattice in which each zinc is surrounded tetrahedrally by four chloride ions, but the low melting point and solubility in organic solvents indicate some covalent... 

The variation of Cp for crystalline thiazole between 145 and 175°K reveals a marked inflection that has been attributed to a gain in molecular freedom within the crystal lattice. The heat capacity of the liquid phase varies nearly linearly with temperature to 310°K, at which temperature it rises more rapidly. This thermal behavior, which is not uncommon for nitrogen compounds, has been attributed to weak intermolecular association. The remarkable agreement of the third-law ideal-gas entropy at... 

FIGURE 1 4 An ionic bond IS the force of attrac tion between oppositely charged ions Each Na ion (yellow) in the crystal lattice of solid NaCI IS involved in ionic bonding to each of six surrounding Cl ions (green) and vice versa... 

Table 4.14 Spatial Orientation of Common Hybrid Bonds Figure 4.1 Crystal Lattice Types Table 4.15 Crystal Structure...

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