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The energy distribution

Again if the number of cells N is much larger than the number of particles, this reduces for three particles to [Pg.193]

From this approximate form we can immediately jump to the conclusion that for iV particles, if N is much larger than N , then, approximately. [Pg.193]

On the other hand, if we need the exact form for Q, Eq. (9.67) can be generalized for Na particles to [Pg.193]

If we multiply this last equation by (N — N ) in both numerator and denominator, it reduces to [Pg.193]

The entropy attending the expansion from N to N cells is easily calculated using Eq. (9.68). For N cells, [Pg.193]


Knowing the energy distributions of electrons, (k), and the spatial distribution of electrons, p(r), is important in obtaining the structural and electronic properties of condensed matter systems. [Pg.101]

Pibel C D, Sirota E, Brenner J and Dai H L 1998 Nanosecond time-resolved FTIR emission spectroscopy monitoring the energy distribution of highly vibrationally excited molecules during collisional deactivation J. Chem. Phys. 108 1297-300... [Pg.1176]

Quenched dynamics is a combination of high temperature molecular dynamics and energy minimization. This process determines the energy distribution of con formational families produced during molecular dynamics trajectories. To provide a better estimate of conformations, you should combine quenched dynamics with simulated annealing. [Pg.78]

I Ikcal/mol. From this initial simulation a histogram is constructed which gives the iber of times a state with an energy in the range E to E + 6E is determined. These histo-a values cire stored in an array H( ). Each of the values in this cirray (H(E)) should initially approximate the energy distribution at the temperature Tq ... [Pg.452]

One of the drawbacks of the multicanonical method is that, during the simulations tc derive the weight factor, the energy distribution in H(E) can oscillate rather than steadilj approaching a limiting distribution. Another drawback is that it can fail to properlj... [Pg.453]

Fig. 2. (a) Energy, E, versus wave vector, k, for free particle-like conduction band and valence band electrons (b) the corresponding density of available electron states, DOS, where Ep is Fermi energy (c) the Fermi-Dirac distribution, ie, the probabiUty P(E) that a state is occupied, where Kis the Boltzmann constant and Tis absolute temperature ia Kelvin. The tails of this distribution are exponential. The product of P(E) and DOS yields the energy distribution... [Pg.344]

At aU but the lowest bombarding energies, the flux of atoms that are sputtered from the surface leaves the surface with a cosine distribution (Fig. 6). The sputtered atoms have kinetic energies higher than those of thermally vaporized atoms, as well as a high energy tail in the energy distribution that can be several tens of eV. [Pg.517]

Electronics has, in fact, been a very fertile area for SEM application. The energy distribution of the SEs produced by a material in the SEM has been shown to shift linearly with the local potential of the surface. This phenomenon allows the SEM to be used in a noncontact way to measure voltages on the surfaces of semiconductor devices. This is accomplished using energy analysis of the SEs and by direedy measuring these energy shifts. The measurements can be made very rapidly so that circuit waveforms at panicular internal circuit nodes can be determined accurately. [Pg.81]

The analyst has two practical means of measuring the energy distribution of X rays emitted from the specimen energy-dispersive spectrometry and wavelength dispersive spectrometry. These two spectrometers are highly complementary the strengths of each compensate for the weaknesses of the other, and a well-equipped electron probe instrument will have both spectrometers. [Pg.179]

Auger electron spectroscopy (AES) is a technique used to identify the elemental composition, and in many cases, the chemical bonding of the atoms in the surface region of solid samples. It can be combined with ion-beam sputtering to remove material from the surface and to continue to monitor the composition and chemistry of the remaining surface as this surface moves into the sample. It uses an electron beam as a probe of the sample surface and its output is the energy distribution of the secondary electrons released by the probe beam from the sample, although only the Ai er electron component of the secondaries is used in the analysis. [Pg.310]

The complete description of the number of Auger electrons that are detected in the energy distribution of electrons coming from a surface under bombardment by a primary electron beam contains many factors. They can be separated into contributions from four basic processes, the creation of inner shell vacancies in atoms of the sample, the emission of electrons as a result of Auger processes resulting from these inner shell vacancies, the transport of those electrons out of the sample, and the detection and measurement of the energy distribution of the electrons coming from the sample. [Pg.313]

For primarily historical reasons people have come to consider Auger spectra as having the form, dN(E)/dEversus E, where N(E) is the energy distribution of the sec-... [Pg.315]

Consider a distribution system that consists of a gaseous mobile phase and a liquid stationary phase. As the temperature is raised the energy distribution curve in the gas moves to embrace a higher range of energies. Thus, if the column temperature is increased, an increasing number of the solute molecules in the stationary phase will randomly acquire sufficient energy (Ea) to leave the stationary phase and enter the... [Pg.12]

Temperature becomes a quantity definable either in terms of macroscopic thermodynamic quantities, such as heat and work, or, with equal validity and identical results, in terms of a quantity, which characterized the energy distribution among the particles in a system. With this understanding of the concept of temperature, it is possible to explain how heat (thermal energy) flows from one body to another. [Pg.3]

Celsius. The energy distribution of the radiation emitted by this surface is fairly close to that of a classical black body (i.e., a perfect emitter of radiation) at a temperature of 5,500°C, with much of the energy radiated in the visible portion of the electromagnetic spectrum. Energy is also emitted in the infrared, ultraviolet and x-ray portions of the spectrum (Figure 1). [Pg.1051]

Given a size N lattice (thought of now as a heat-bath), consider some subsystem of size n. An interesting question is whether the energy distribution of the subsystem, Pn E), is equal to the canonical distribution of a thermodynamic system in equilibrium. That is, we are interested in comparing the actual energy distribution... [Pg.385]

Elastic scattering within the dark space is generally assumed (7) not to affect the energy distribution of the ions seriously. This is apparently caused by the low scattering angles involved which result in little or no momentum transfer. [Pg.325]


See other pages where The energy distribution is mentioned: [Pg.317]    [Pg.93]    [Pg.1306]    [Pg.2247]    [Pg.2797]    [Pg.108]    [Pg.356]    [Pg.448]    [Pg.449]    [Pg.320]    [Pg.2280]    [Pg.297]    [Pg.137]    [Pg.279]    [Pg.303]    [Pg.314]    [Pg.322]    [Pg.503]    [Pg.503]    [Pg.99]    [Pg.117]    [Pg.10]    [Pg.412]    [Pg.108]    [Pg.182]    [Pg.132]    [Pg.132]    [Pg.200]    [Pg.43]    [Pg.105]    [Pg.251]    [Pg.325]    [Pg.325]   


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Energy distribution

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