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Energy of creation

The energy of creation of a disorder is determined on the basis of a Bom-Haber cycle. We will look at the example of formation of the doubly-ionized Schottky disorder. We envisage the following Bom-Haber cycle ... [Pg.188]

It is clear that if we wish to calculate, say, the energy of creation of a vacancy, we need to be able to calculate a lattice energy of a solid with and without the defect. The difference between these two terms would give us the energy of formation of the defect. We now begin to see the first difficulty the result we are seeking is the difference between two significant numbers, so obviously, we need a preeise measure of each of them. [Pg.189]

Thus, we can see that in order to calculate the energy of creation of the defect, it is clearly necessary to have a potential function but also to be capable of taking account of the relaxations and polarization of the atoms or ions placed around the defect. [Pg.190]

Here ak a ) is the annihilation (creation) operator of an exciton with the momentum k and energy Ek, operator an(a ) annihilates (creates) an exciton at the n-th site, 6,(6lt,) is the annihilation (creation) operator of a phonon with the momentum q and energy u) q), x q) is the exciton-phonon coupling function, N is the total number of crystal molecules. The exciton energy is Ek = fo + tfcj where eo is the change of the energy of a crystal molecule with excitation, and tk is the Fourier transform of the energy transfer matrix elements. [Pg.445]

Whether this concept can stand up under a rigorous psychological analysis has never been discussed, at least in the literature of theoretical physics. It may even be inconsistent with quantum mechanics in that the creation of a finite mass is equivalent to the creation of energy that, by the uncertainty principle, requires a finite time A2 A h. Thus the creation of an electron would require a time of the order 10 20 second. Higher order operations would take more time, and the divergences found in quantum field theory due to infinite series of creation operations would spread over an infinite time, and so be quite unphysical. [Pg.450]

The Brueckner-reference method discussed in Section 5.2 and the cc-pvqz basis set without g functions were applied to the vertical ionization energies of ozone [27]. Errors in the results of Table IV lie between 0.07 and 0.17 eV pole strengths (P) displayed beside the ionization energies are approximately equal to 0.9. Examination of cluster amplitudes amd elements of U vectors for each ionization energy reveals the reasons for the success of the present calculations. The cluster operator amplitude for the double excitation to 2bj from la is approximately 0.19. For each final state, the most important operator pertains to an occupied spin-orbital in the reference determinant, but there are significant coefficients for 2h-p operators. For the A2 case, a balanced description of ground state correlation requires inclusion of a 2p-h operator as well. The 2bi orbital s creation or annihilation operator is present in each of the 2h-p and 2p-h operators listed in Table IV. Pole strengths are approximately equal to the square of the principal h operator coefiScient and contributions by other h operators are relatively small. [Pg.48]

This expression is derived as the Fourier transform of a time-dependent one-particle autocorrelation function (26) (i.e. propagator), and cast in matrix form G(co) over a suitable molecular orbital (e.g. HF) basis, by means of the related set of one-electron creation (ai" ") and annihilation (aj) operators. In this equation, the sums over m and p run over all the states of the (N-1)- and (N+l)-electron system, l P > and I P " respectively. Eq and e[ represent the energy of the... [Pg.79]

The several industrial applications reported in the hterature prove that the energy of supersonic flow can be successfully used as a tool to enhance the interfacial contacting and intensify mass transfer processes in multiphase reactor systems. However, more interest from academia and more generic research activities are needed in this fleld, in order to gain a deeper understanding of the interface creation under the supersonic wave conditions, to create rehable mathematical models of this phenomenon and to develop scale-up methodology for industrial devices. [Pg.300]

For an atom in a solid, vibratory motion involves potential energy as well as kinetic ener, and both modes will contribute a term l/2kT, resulting in an average total energy of 3kT. Thus, it is the entropy of mixing that forces the creation of a certain number of vacant lattice positions above 0.0 °K. Hence, vacancies are the natural resultof thermod5mamic equilibrium md not the result of accidental growth or sample preparation. [Pg.125]


See other pages where Energy of creation is mentioned: [Pg.32]    [Pg.24]    [Pg.391]    [Pg.32]    [Pg.597]    [Pg.70]    [Pg.393]    [Pg.215]    [Pg.18]    [Pg.326]    [Pg.381]    [Pg.282]    [Pg.96]    [Pg.187]    [Pg.188]    [Pg.151]    [Pg.560]    [Pg.32]    [Pg.24]    [Pg.391]    [Pg.32]    [Pg.597]    [Pg.70]    [Pg.393]    [Pg.215]    [Pg.18]    [Pg.326]    [Pg.381]    [Pg.282]    [Pg.96]    [Pg.187]    [Pg.188]    [Pg.151]    [Pg.560]    [Pg.46]    [Pg.340]    [Pg.347]    [Pg.153]    [Pg.160]    [Pg.608]    [Pg.451]    [Pg.37]    [Pg.182]    [Pg.192]    [Pg.138]    [Pg.7]    [Pg.16]    [Pg.315]    [Pg.54]    [Pg.368]    [Pg.387]    [Pg.506]    [Pg.111]    [Pg.56]    [Pg.797]    [Pg.525]    [Pg.75]    [Pg.72]    [Pg.515]   


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