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Energy spectrum definition

By substituting back into the definition of a , we get the solution set for the energy spectrum Ei. In ethylene there are two elements on the diagonal, xu and X22, leading to Ei and 2- In larger conjugated n systems, there will be more. [Pg.188]

According to the electronic theory, a particle chemisorbed on the surface of a semiconductor has a definite affinity for a free electron or, depending on its nature, for a free hole in the lattice. In the first case the chemisorbed particle is presented in the energy spectrum of the lattice as an acceptor and in the second as a donor surface local level situated in the forbidden zone between the valency band and the conduction band. In the general case, one and the same particle may possess an affinity both for an electron and a hole. In this case two alternative local levels, an acceptor and a donor, will correspond to it. [Pg.159]

In Fig. 2, the normalized model scalar energy spectrum is plotted for a fixed Reynolds number (ReL = 104) and a range of Schmidt numbers. In Fig. 3, it is shown for Sc = 1000 and a range of Reynolds numbers. The reader interested in the meaning of the different slopes observed in the scalar spectrum can consult Fox (2003). By definition, the ratio of the time scales is equal to the area under the normalized scalar energy spectrum as follows ... [Pg.242]

By definition, the turbulent kinetic energy k can be found directly from the turbulent energy spectrum by integrating over wavenumber space ... [Pg.56]

From the definition of the turbulent energy spectrum, e is related to Eu k, t) by... [Pg.57]

This equation has the same contributions of order (Za)" as in (3.4), but formally this expression also contains nonrecoil and recoil corrections of order Zaf" and higher. The nonrecoil part of these contributions is definitely correct since the Dirac energy spectrum is the proper limit of the spectrum of a two-particle system in the nonrecoil limit m/M = 0. As we will discuss later the first-order mass ratio contributions in (3.5) correctly reproduce recoil corrections of higher orders in Za generated by the Coulomb and Breit exchange photons. Additional first order mass ratio recoil contributions of order (Za) ... [Pg.21]

To use this method, the system of equations (4) must be complemented by the functions relate material parameters a, a and k to the impurity concentration N ,p and temperature.The more accurate the definition of these relations, the higher the accuracy of the Special investigations have been conducted based on our empirical data and the data from the world literature that allowed to approximate the functions of On,p, Cn,p and K ,p by the method. These relations are dictated by the energy spectrum of material, microscopic constants of substance and the character of current carrier scattering, polynomials. [Pg.505]

In the low-energy (IR) region of the spectrum, definite materials limitations are encountered which have in the past permitted only marginal response beyond about 1 pm [5.11]. As this chapter shows, however, substantial recent advances have been made in increasing red sensitivity and in extending IR response out to and beyond 1.5 pm [5.12] indeed this chapter concentrates on these most recent advances into the near-infrared region of the spectrum [5.4, 13-21] where nonphotoemissive detectors previously were the only choice. [Pg.150]

Since only information on the energy spectrum and wave functions of the ground multiplets is necessary for interpretation and prediction of magnetic properties of lanthanide compounds, and bearing in mind an essential role of electron-phonon interaction, we shall confine ourselves in this case to semiphenomenological models of the crystal field which allow one to represent parameters Bpq as definite functions of structural parameters of the crystal lattice. All the models developed until recently are... [Pg.312]

If we assume that, in first approximation, the neutron-energy spectrum is the same for all r, and in fact varies as l/ , then it follows from the above expression that an acceptable definition of D would be... [Pg.459]

Here, U is the internal energy and T the temperature. On another hand, there is a definition of the Helmholtz free-energy from a statistical approach [12]. Given a system with an energy spectrum , the Helmholtz free-energy is defined as ... [Pg.18]

Figure 11.2(b) depicts the energy spectrum of a turbulent signal. This curve verifies several essential properties. Function E f ) is always positive, as per its definition (equation [11.4]). It is also found that function E f ) tends toward 0 for n 00. This property results from the Parceval equality ... [Pg.211]

The energy spectrum of electrons emitted by a specimen in an electron beam has two maxima. One is at high energy where most of the back-scattered electrons are, and the other is at only a few eV. These are secondary electrons, which by definition include all electrons emitted at less than 50 eV. The number emitted divided by the number of incident electrons is the secondary emission coefficient 5. For 20keV incident electrons in the SEM, the coefficient is close to... [Pg.89]

Calculation of chromaticity coordinates then proceeds as described above for sources. If an equal-energy spectrum is assumed, the source term S X) can be dropped fi om the definition of (j) X). When the chromaticity of a surface is specified without specification of the source, an equal-energy spectrum is usually implied. [Pg.14]


See other pages where Energy spectrum definition is mentioned: [Pg.57]    [Pg.73]    [Pg.97]    [Pg.14]    [Pg.23]    [Pg.38]    [Pg.54]    [Pg.97]    [Pg.44]    [Pg.60]    [Pg.303]    [Pg.44]    [Pg.174]    [Pg.335]    [Pg.437]    [Pg.66]    [Pg.349]    [Pg.113]    [Pg.23]    [Pg.434]    [Pg.110]    [Pg.240]    [Pg.5]    [Pg.126]    [Pg.463]   
See also in sourсe #XX -- [ Pg.37 , Pg.71 ]

See also in sourсe #XX -- [ Pg.37 , Pg.71 ]




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Definition of Energy Spectra

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