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Secondary quantization

The formal secondary quantisation procedure presented first by Doi [107], Zeldovich and Ovchinnikov [35] reduces equations (2.3.67) into [Pg.132]

The state of a system in this equation is given by wave function  [Pg.132]

Taking into account the symmetry of with respect [Pg.132]

The standard expansion of operators + into plane waves [Pg.133]

Bose birth-death (creation-annihilation) operators a-, at, b, bt  [Pg.133]


Here /(R) and pflX) denote the shift and generalized momentum for the molecular vibration of the low frequency a>9 and reduced mass m, at the Rth site of the adsorbate lattice bi+(K) and K) are creation and annihilation operators for the collectivized mode of the adsorbate that is characterized by the squared frequency /2(K) = ml + d>, a,(K)/m , with O / iat(K) representing the Fourier component of the force constant function /jat(R). Shifts i//(R) for all molecules are assumed to be oriented in the same arbitrary direction specified by the unit vector e they are related to the corresponding normal coordinates, ue (K), and secondary quantization operators ... [Pg.81]

The considerable progress made in the studies of simple bimolecular reactions (which has led to such fundamental conclusions) was achieved by a more rigorous mathematical treatment of the problem, avoiding the use of the simplest approximations which linearize the kinetic equations. We focus main attention on the many-point density formalism developed in [26, 28, 49] since in our opinion it seems at present to be the only general approach permitting treatment of all the above-mentioned problems, whereas other theoretical methods so far developed, e.g., those of secondary quantization [19, 29-32], and of multiple scattering [72, 73], as well based on... [Pg.620]

In accordance with the secondary quantization technique, the operator if/ can be presented in the form ... [Pg.121]

In the course of study, students should master material that is both simple and complex. Much of this involves familiarity with the set of mathematical tools repeatedly used throughout this book. The Appendices provide ample reference to such a toolbox. These include matrix algebra, determinants, vector spaces, vector orthogonalization, secular equations, matrix diagonalization, point group theory, delta functions, finding conditional extrema (Lagrange multipliers, penalty function methods), Slater-Condon rules, as well as secondary quantization. [Pg.1116]

It is interesting to note that this is the first time that in the present framework the quantization is formed by two quantum numbers a number n to be termed the principal quantum number and a number , to be termed the secondary quantum number. This case is reminiscent of the two quantum numbers that characterize the hydrogen atom. [Pg.657]

Both the 12C/13C primary KIE and the 14N/15N secondary KIE have been determined (Table 4-2) [19, 20], with the immediate adjacent atoms about the isotopic substitution site quantized as well. To our knowledge, we are not aware of any such simulations prior to our work for a condensed phase reaction with converged secondary heavy isotope effects. This demonstrates the applicability and accuracy of the PI-FEP/UM method. [Pg.99]

Consider a quantized field with discrete energy levels, each occupied by a characteristic number of molecules. These numbers can be thought of as representing relative activities during the course of a hypothetical reaction that starts with n molecules at the initial energy level Ui and reaching equilibrium with rij molecules of the final product at the level Uj. Intermediate levels are occupied by secondary products. As before... [Pg.253]

The other quantum number, Mj, describing the same angular momentum is of course its projection in some direction, called the quantization axis, which is chosen for our convenience. There are 2/+1 values allowed for the secondary spin quantum number —/, —/+1,. .., /—1, /. One can usefully think of a classical analogue of opJ vector J, as precessing about the axis of quantization. [Pg.3]

The advantages of SIMS are its high sensitivity (detection limit of ppm for certain elements), its ability to detect hydrogen and the emission of molecular fragments which often bear tractable relationships with the parent structure on the surface. Disadvantages are that secondary ion formation is a poorly understood phenomenon and that quantization is often difficult. A major drawback is the matrix effect secondary ion yields of one element can vary tremendously with its chemical environment. TTiis matrix effect and the elemental sensitivity variation of five orders of magnitude across the periodic table make quantitative interpretation of SIMS spectra of technical catalysts extremely difficult. [Pg.506]

Bohr felt instinctively that Planck s quantized energies were related to the discrete lines of elemental spectra— and to the planetary model of the atom— but he could not find the connection. Thirty years earlier Johann Jakob Balmer, a teacher at a girls secondary school, part-time lecturer at the University of Basel (where, we may note, Paracelsus burned the works of Galen), and mathematics hobbyist had found a numerical relationship between frequencies of the lines in the hydrogen spectrum. The relationship was not obvious because it depended on the reciprocal squares of integers, and this was the very feature that caught Bohr s attention. He later said, As soon as I saw Balmer s formula, the whole thing was immediately clear to me. ... [Pg.319]


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Quantization

Quantized

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