Static defects

Static defects scatter elastically the charge carriers. Electrons do not loose memory of the phase contained in their wave function and thus propagate through the sample in a coherent way. By contrast, electron-phonon or electron-electron collisions are inelastic and generally destroy the phase coherence. The resulting inelastic mean free path, Li , which is the distance that an electron travels between two inelastic collisions, is generally equal to the phase coherence length, the distance that an electron travels before its initial phase is destroyed ... 

Under the simulation conditions, the HMX was found to exist in a highly reactive dense fluid. Important differences exist between the dense fluid (supercritical) phase and the solid phase, which is stable at standard conditions. One difference is that the dense fluid phase cannot accommodate long-lived voids, bubbles, or other static defects, whereas voids, bubbles, and defects are known to be important in initiating the chemistry of solid explosives.107 On the contrary, numerous fluctuations in the local environment occur within a time scale of tens of femtoseconds (fs) in the dense fluid phase. The fast reactivity of the dense fluid phase and the short spatial coherence length make it well suited for molecular dynamics study with a finite system for a limited period of time chemical reactions occurred within 50 fs under the simulation conditions. Stable molecular species such as H20, N2, C02, and CO were formed in less than 1 ps. 

Well-studied static defects in insulating ionic crystals (e.g., NaCl) are various centers (i) F (for Farbzentrum) center one trapped electron... 

A whole class of models involving localization by phonons and static defects has been reviewed by Abrikosov and Ryzkhin [49]. These models also give a T2 law for P/,(T) in the weak inelasticity limit when 0)ot 1, where phonon frequency and 1/t is the total electron scattering rate. Roughly speaking, these models reflect the strong tendency... 

In normal metals such as copper the conductivity rises as the temperature is reduced from room temperature to about 10 K and then remains constant. The conductivity rises as the phonon scattering of free electrons is reduced as the thermally activated phonons are frozen out at low temperatures. The constant value at very low temperature results from scattering by the static defect... 

Wi = electronic thermal resistivity due to phonon interaction with conduction electrons Wo = electronic thermal resistivity due to static defects Wp = lattice thermal resistivity due to point defects... 

At these temperatures is determined by conduction electron scattering on static defects (Klemens 1969) and... 

Belitsky and Goltscv 1991, Bhatlachaijee et al. 1989, Raki et al. 1990), and the specific behaviour of L(T) intrinisic only in these systems has been predicted (or explained, if experimental data had been obtained previously). Analysing experimental data on L(T) of CKL and DKL systems one must remember that in normal metals L = Lq due to the scattering of electrons by static defects, and L < Lq in the low-temperature region due to... 

In nontransition metals and alloys the electron mean fi"ee path is usually so large that the standard Boltzmann equation suffices to describe the electrical resistivity. However, both pure transition metals and their alloys and compounds often show a saturation of the resistivity when the mean free path becomes short. A further increase in the lattice disorder through more alloying atoms, more static defects, or larger atomic vibrations caused by increased temperature will not have a significant effect on the total resistivity. The temperature dependence of the resistivity p in such a material approaching resistivity saturation is sometimes well described by the empirical parallel resistor formula due to Wiesmann et al. (18) ... 

Static defects in CVD diamonds such as stacking faults, dislocations, twinning, hydrogen, and other impurity atoms introduce displacement disorder of the carbon atoms. They cause shifts of atoms from the equilibrium positions. Static disturbances of lattice periodicity are the cause of X-ray or electron diffuse scattering. The intensity of diffuse scattering is a direct measure of the departure from the periodic network. The diffuse scattering around the 111 reciprocal lattice point is a very sensitive test for lattice periodicity of a CVD single crystal. 

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