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Formal Consideration

Before discussing the interaction of a molecule with an electromagnetic field in detail, it is useful to review some formal facts about electromagnetic radiation. When radiative decay processes are considered, the molecular Hamiltonian of the system molecule plus radiation field is given by [Pg.129]

The operator Hei or Hbo is the Hamiltonian for the internal electronic states of the molecule (which include electronic, vibrational, and rotational states). If the initial [Pg.129]

Hint is the radiation-matter interaction term taken as [Pg.130]

The sum on k here extends over all plane wave momentum states k in the cavity of volume V. The only nonvanishing matrix elements of ak,g and o. are [Pg.130]

In discussing the electromagnetic interaction of a charged particle with the radiation field, the zero-order states are taken as eigenstates of the Hamiltonian  [Pg.130]


Some Formal Considerations. As with most natural toxins, detection methods for the saxitoxins are an essential prerequisite for most studies of them, as well as for monitoring programs to ensure the safety of food products that may contain them. Furthermore, the degree of success of such efforts is dependant on the characteristics of the detection method used. Detection of the saxitoxins is particularly challenging because of the large number of different but related compounds that must be dealt with, the low levels that must be detected, and their chemical characteristics. Given these factors it is useful to dwell briefly on some underlying principles. [Pg.43]

All results are based upon master eq. (16). One of the chief deficiencies of many discussions of chemical transitions of excited molecules is made apparent by the formalism. Considerable effort has been devoted to development of electronic wave functions for A and B. Transition probabilities are then discussed in terms of superficial examination of the relationships between the wave functions. In discussions of the subject, considerable bickering may arise because of divergence of opinion as to the goodness of electronic wave functions. While discussion of the quality of approximate wave functions has real significance in structural chemistry, it seems to be a matter of secondary importance in treatment of the dynamic problem at the present time. Almost any kind of electronic wave function is likely to be of better quality than any available perturbation operators (// ). A secondary problem arises from the fact that the vibrational part of ifi1, is likely to be relatively unknown.)- At the present time our best approach to the problem appears to be use of experiments to read back the nature of the perturbation. This leads to an iterative procedure in which the implications of relationships between wave functions are examined experimentally to lead to tentative generalizations that are, in turn, used to predict results of more experiments. The procedure is essentially that used by Zimmerman and his group,7 by Woodward and Hoffman,25 and, in one form or another, by various other authors. [Pg.382]

For many formal considerations this compact operator formulation is more convenient. For example, it is possible to write a formal solution of this equation in the form... [Pg.185]

Let us start with some purely formal considerations. Let us consider a linear space A = and an operator U defined on this space, which maps it onto itself in a one-to-one way, so that... [Pg.88]

It must be noted that the expression (5.14) was obtained in Ref.36) not as a result of the smoothing procedure, but with the help of some other more formal consideration. The main idea of this consideration can be outlined as follows. It is well known24 that the smoothing procedure for the model of beads leads to the operator of the type g a= 1 + a2 A, and in the same approximation the partition function reduces to the Wiener integral33 . In Ref.36) it was shown that the role of the operator (5.14) for the integration over the space of smooth curves is the same as the role of the Laplace operator for the usual Wiener integral... [Pg.86]

Archimedean solid in a formal consideration (middle). One tetrahedrally coordinated O atom as in liquid water is also emphasized (bottom). [Pg.471]

Another way to apply the same idea can be derived from formal considerations. We now consider a double well system that correspond to the reaction 7 P and suppose that we can generate trajectories as before. Define the population function... [Pg.526]

In summary then, the mode of species identification is largely dictated by the particular reaction being studied and the experimental conditions. This chapter illustrates how the formal considerations above can be implemented in a theory of reactions in liquids. [Pg.88]

There are also compelling reasons for the introduction of these fields from more formal considerations. The usefulness of the linear response formulation in Section V hinges on the assumption that the linear density fields vary more slowly than other variables in the system. It is known that this is not the case even for fields that are conserved in the zero wave vector limit. Consider, for instance, the solute density field n (k) for a nonreacting fluid. As discussed in Section V, for small k this field will decay slowly in time. But so will the product field n (q) (k—q), provided both k and q are small, since... [Pg.111]

The computational "phenomenon" of the OCL MCHF configurations can be understood from formal considerations as follows, [37b, p. 463] and [77]. [Pg.230]

One advantage of holistic comparison is that it requires no formal consideration of probability or utQity. Consequently, decision makers unfamiliar with these concepts may find hoUstic comparison to be more intuitive, and potential violations of the axioms underlying SEU and MAUT, due to their lack of understanding, become of lesser concern. People seem to find the holistic approach helpful when they compare complex alternatives (Janis and Mann 1977). In fact, people may feel there is little additional benefit to be obtained from sepeuately analyzing the probability and value attached to each attribute. This tendency becomes prevtilent in naturalistic decision meiking, as addressed further in Section 5. [Pg.2184]

A formal consideration of Eq. (5) predicts the infinitely large limiting value of the Galvani potential (A —oo) when the activity of metal ions approaches zero (a hypothetical solution containing no ions of this sort, or pure solvent). However, this is not the case, because the limit of thermodynamic stability of the solvent will be exceeded. For an ideal thermodynamically stable (hypothetical) solution, this uncertainty can be clarified, if the electronic equilibria between the metal and the solvent are taken into account, which requires the consideration of solvated electrons (eg) [7-11]. The latter are... [Pg.5]

RATE CONSTANTS AND CROSS SECTIONS—SOME FORMAL CONSIDERATIONS... [Pg.110]

Short Overview of Basic Properties and Formal Considerations I 337... [Pg.337]

A. General definitions and formal considerations on adsorption and catalysis ... [Pg.45]

Formal consideration of the Social Responsibility concept by senior executives is a fairly recent development. What is Social Responsibility An Internet search engine will reveal a large number of definitions. For the purposes of this chapter, two definitions have been chosen. [Pg.120]

Korte C, Schichtel N, Hesse D, Janek J (2009) Influence of interface stmcture on mass transport in phase boundaries between different ionic materials experimental studies and formal considerations. Monatshefte Fur Chemie 140(9) 1069-1080... [Pg.682]


See other pages where Formal Consideration is mentioned: [Pg.192]    [Pg.194]    [Pg.296]    [Pg.298]    [Pg.28]    [Pg.193]    [Pg.571]    [Pg.87]    [Pg.9]    [Pg.162]    [Pg.181]    [Pg.250]    [Pg.330]    [Pg.31]    [Pg.26]    [Pg.25]    [Pg.250]    [Pg.204]    [Pg.223]    [Pg.1217]    [Pg.296]    [Pg.298]    [Pg.8]    [Pg.89]    [Pg.185]    [Pg.151]    [Pg.217]    [Pg.6]    [Pg.161]   


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