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A Correspondence Principle

A striking analogy exists between localized molecular orbital, electron-domain models of organic and other covalently bonded molecules (Figs. 3—8) and ion-packing models of inorganic compounds 47). [Pg.8]

These results may be generalized in a Principle of Correspondence There exists an isomorphism between the ion-packing model of heteropolar compounds and the electron-pair model of homopolar compounds. This correspondence is summarized in Table I. [Pg.9]

Sizes and shapes approximately independent of chemical environment. [Pg.9]

Negatively charged bodies. Generally larger and more polarizable than cations. [Pg.9]

Valence-shell electron-pairs. Charge —2 if unprotonated, —1 if protonated. [Pg.9]


In principle many different approaches can be used to handle this equation we use a correspondence principle. In the case of no energetic interactions this model should be equivalent to the model discussed in Section 9.1.1. This results in the condition... [Pg.567]

This conjecture did not feature explicitly in Bohr s original argument, which he based on a correspondence principle, and only emerged in later work. [Pg.24]

When first confronted with the oddities of quantum effects Bohr formulated a correspondence principle to elucidate the status of quantum mechanics relative to the conventional mechanics of macroscopic systems. To many minds this idea suggested the existence of some classical/quantum limit. Such a limit between classical and relativistic mechanics is generally defined as the point where the velocity of an object v —> c, approaches the velocity of light. By analogy, a popular definition of the quantum limit is formulated as h —> 0. However, this is nonsense. Planck s constant is not variable. [Pg.50]

A corresponding principle applies to controlled radical polymerisation performed in quite a number of modes such as nitroxide-mediated polymerisation (NMP), atom transfer radical polymerisation (ATRP), reversible addition fragmentation chain transfer (RAFT) or catalytic chain transfer (CCT) reactions. All of these variants of controlled radical polymerisation lead to well-defined architectures with the particular advantage that a much larger number of monomers are suitable and the reaction conditions are much less demanding than those of living ionic polymerisation reactions. [Pg.3]

In case T" were not available, even at ambient temperature and pressure, a correspondence principle was proposed by Shock and Helgeson (Shock and Helgeson, 1988), which correlates the standard ionic partial molar volume with the conventional standard ionic entropy. [Pg.154]

A = /jc/ photon> h has the form of de Broglie s equation AdB =h/p but is written for radiation instead of matter. We ve used de Broglie s equation to devise a correspondence principle to tell us when we need to use quantum mechanics to describe a system. Does this form of Planck s law suggest a version of the correspondence principle appropriate for radiation ... [Pg.63]

Stress analysis procedures for materials having homogeneous constitutive equations are developed in Section 5. Here a correspondence principle is developed for proportional stress boundary valued problems demonstrating that for large classes of these constitutive equations linear analysis methods can be used to obtain the stress distribution, while the strain distribution must be obtained from the non-linear constitutive equation. In section 6 the theory is applied to experimental data and shown to yield accurate stress predictions for a variety of strain inputs. [Pg.342]

The procedure described above is an application of the time-temperature correspondence principle. By shifting a set of plots of modulus (or compliance) versus time (or frequency) at any temperature (subscript 1) along the log t axis, we obtain the value of that mechanical property at another time and temperature (subscript 2). Using the shear modulus as an example, the time-temperature correspondence principle states... [Pg.258]

The classical model predicts that the largest probability of finding a particle is when it is at the endpoints of the vibration. The quantum-mechanical picture is quite different. In the lowest vibrational state, the maximum probability is at the midpoint of the vibration. As the quantum number v increases, then the maximum probability approaches the classical picture. This is called the correspondence principle. Classical and quantum results have to agree with each other as the quantum numbers get large. [Pg.32]

Strictly, the strain gauges referred to above come into this category, since in such cases the change in the measured quantity causes a corresponding change in the resistance of the element. However, the principle has a much wider application, using changes in either the inductive or capacitive reactance of electrical circuit elements. [Pg.244]

Consider next the current operator ju(x). The correspondence principle suggests that its form is j ( ) = — (e/2)( ( )yB, (a )]. Such a form foijn(x) does not satisfy Eq. (11-477). In fact, due to covariance, the spectral representation of the vacuum expectation value of 8u(x)Av(x), where ( ) is an arbitrary four-vector, is given by... [Pg.704]

For every positive term there is a corresponding negative one, a manifestation of the principle of microscopic reversibility, discussed further in Section 7.8. [Pg.129]

The original semiclassical version of the centrifugal sudden approximation (SCS) developed by Strekalov [198, 199] consistently takes into account adiabatic corrections to IOS. Since the orbital angular momentum transfer is supposed to be small, scattering occurs in the collision plane. The body-fixed correspondence principle method (BFCP) [200] was used to write the S-matrix for f — jf Massey parameter a>xc. At low quantum numbers, when 0)zc —> 0, it reduces to the usual non-adiabatic expression, which is valid for any Though more complicated, this method is the necessary extension of the previous one adapted to account for adiabatic corrections at higher excitation... [Pg.166]

It is now shown how the abrupt changes in the eigenvalue distribution around the central critical point relate to changes in the classical mechanics, bearing in mind that the analog of quantization in classical mechanics is a transformation of the Hamiltonian from a representation in the variables pR, p, R, 0) to one in angle-action variables (/, /e, Qr, 0) such that the transformed Hamiltonian depends only on the actions 1r, /e) [37]. Hamilton s equations diR/dt = (0///00 j), etc.) then show that the actions are constants of the motion, which are related to the quantum numbers by the Bohr correspondence principle [23]. In the present case,... [Pg.46]

According to the correspondence principle as stated by N. Bohr (1928), the average behavior of a well-defined wave packet should agree with the classical-mechanical laws of motion for the particle that it represents. Thus, the expectation values of dynamical variables such as position, velocity, momentum, kinetic energy, potential energy, and force as calculated in quantum mechanics should obey the same relationships that the dynamical variables obey in classical theory. This feature of wave mechanics is illustrated by the derivation of two relationships known as Ehrenfest s theorems. [Pg.43]

The extent of validation of confirmatory techniques is currently under consideration. Qne approach is that the extent of validation may be smaller than for the enforcement method. In principle, validation in triplicate at the relevant concentration level (LOQ or MRL) is sufficient. In the case where an MRL is set for multiple crops, a single validation in all representative crop groups is sufficient. A confirmatory method for residues in air is not required if a corresponding method was submitted for the other sample matrices. This approach is realized in Germany. ... [Pg.28]


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