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Wave nature of particles

As the name suggests, shape-type resonances result from the shape of the potential at hand. But, what attributes must a potential have in order to trap the particle for a finite time and thus form a metastable state The wave nature of particles in quantum mechanics provides two typical ways for a... [Pg.24]

Electron diffraction Electron diffraction demonstrated the wave nature of particles. [Pg.160]

A formal method of dealing with the wave nature of particles was developed by Irwin Schrodinger in 1926. A greatly simplified derivation of the time-independent Schrodinger wave equation is presented in Section 2.3. [Pg.18]

Louis Victor de Broglie (1892-) extended the dual character of light (wave and corpuscular) to matter. In 1924 he proposed that an electron in motion (as in a Bohr orbit) had a wave associated with it. C. J. Davisson, L. H. Germer, and G. P. Thomson found experimental evidence for this wave nature of particles in 1927 (Holum 1969, p. 37). [Pg.24]

Ligand A molecule or anion bonded to the central metal in a complex ion, 409 characterization, 411-412 nomenclature, 648-649 Light, 159q absorption, 421 particle nature of, 135-136 wave nature of, 133-135 Limiting reactant The least abundant... [Pg.691]

In classical mechanics both the position of a particle and its velocity at any given instant can be determined with as much accuracy as the experimental procedure allows. However, in 1927 Heisenberg introduced the idea that the wave nature of matter sets limits to the accuracy with which these properties can be measured simultaneously for a very small particle such as an electron. He showed that Ax, the product of the uncertainty in the measurement of the position x, and Ap, the uncertainty in the measurement of the momentum p, can never be smaller than M2tt ... [Pg.53]

Was this your answer Moving According tode Broglie, particles of matte1 behave like waves by virtue of their motion.The wave nature of electrons in atoms is pronounced because electrons move at speeds of about 2 million meters per second. [Pg.156]

Wavefunctions of electrons in atoms are called atomic orbitals. The name was chosen to suggest something less definite than an orbit of an electron around a nucleus and to take into account the wave nature of the electron. The mathematical expressions for atomic orbitals—which are obtained as solutions of the Schrodinger equation—are more complicated than the sine functions for the particle in a box, but their essential features are quite simple. Moreover, we must never lose sight of their interpretation, that the square of a wavefunction tells us the probability density of an electron at each point. To visualize this probability density, we can think of a cloud centered on the nucleus. The density of the cloud at each point represents the probability of finding an electron there. Denser regions of the cloud therefore represent locations where the electron is more likely to be found. [Pg.166]

If one considers the wave nature of light, one may think that the photon size is roughly equal to its wavelength (say 500 nm) however, when the photon is absorbed by an atom, it "disappears" within a body of radius 0.5 nm this is a manifestation of the intricacies of the wave-particle duality, which are discussed in Section 3.39. [Pg.69]

I ve been using marbles and atom-size insects as an analogy for electrons, but I don t want to leave you with the misconception that electrons can only be thought of as solid objects. In the introduction to this book and in the first chemistry book, I discussed how we can think of electrons (and all particles, for that matter) as collections of waves. It is this wave nature of electrons that is the basis for quantum mechanics, which is the math we use to come up with the uncertainty principle. So, while it is often convenient to consider electrons to be tiny, solid objects, you should always be aware of the model of electrons as waves. [Pg.48]

The interference of microscopic particles leads to a diffraction pattern with deviations with respect to the mere sum of the individual probabilities. The two events are no longer independent. If we wish to state in advance where the next particle will appear, we are unable to do so. The best we can do is to say that the next particle is more likely to strike in one area than another. A limit to our knowledge, associated with the wave-matter duality, becomes apparent. In the double-slit experiment, we may know the momentum of each particle but we do not know an5 hing about the way the particles traverse the slits. Alternatively, we could think of an experiment that would enable us to decide through which slit the particle has passed, but then the experiment would be substantially different and the particles would arrive at the screen with different distributions. In particular, the two slits would become distinguishable and independent events would occur. No interference would be detected, that is, the wave nature of the particle would be absent. In such an experiment, in order to obtain information about the particle position just beyond the slits, we would change its momentum in an unknown way. Indeed, recent experiments have shown that interference can be made to disappear and reappear in a quantum eraser (ref. 6 and references therein). [Pg.9]

Nobel laureate in Physics) in 1924. In quantum mechanics, two ensembles which show the same distributions for all the observables are said to be in the same state. Although this notion is being introduced for statistical ensembles, it can also be applied to each individual microsystem (see, for example, ref. 8), because all the members of the ensemble are identical, non-interacting and identically prepared (Fig. 1.4). Each state is described by a state function, ip (see, for example, ref. 3). This state function should contain the information about the probability of each outcome of the measurement of any observable of the ensemble. The wave nature of matter, for example the interference phenomena observed with small particles, requires that such state fimctions can be superposed just like ordinary waves. Thus, they are also called wavefunctions and act as probability amplitude functions. [Pg.11]

Under what circumstances does the wavelike nature of particles become apparent When waves from two sources pass through the same region of space, they interfere with each other. Consider water waves as an example. When two crests meet. [Pg.136]

One can conceive various experimental arrangements to demonstrate the wave-nature of material particles and many interferometers have already been built for molecules as mentioned in Sec. 1. However, all these arrangements needed well collimated beams or experimentally distinguishable internal states in order to separate the various diffraction orders. This requirement makes them less suitable for large clusters and molecules for which brilliant sources and highly efficient detection schemes still have to be developed. [Pg.339]

If one wants to observe the wave nature of even more massive molecules brilliant beams are needed that have a low molecular velocity. In practice one will hardly be able to work with de Broglie wavelengths less than 100 fm. For particles in the mass range of 105 amu this requires velocities of the order of vm = 10 rmm/s. Although this is a rather demanding requirement it seems not impossible to develop appropriate sources in the future. Moreover, a realistic earth-bound interferometer would be limited to a Talbot length of the order of one meter. [Pg.352]

Footnote The Wave Nature of the Electron. So far the electron has been considered as a particle, with clearly quantised energy levels, that can be precisely measured, as in the emission lines of the spectrum of hydrogen. Because the electron is so small and light, the accuracy with which it can be measured is very uncertain. This is associated with the Heisenberg Uncertainty Principle, which states that it is impossible to determine both the position and momentum of an electron simultaneously , i.e. Ax Ap = hl2it, where Ax is the uncertainty in measuring the position of the electron and Ap is the uncertainty in measuring the momentum (p = mass X velocity) of the electron. The two uncertainties bear an inverse relationship to each other. Consequently, if the position of the... [Pg.19]

The experimental and theoretical work on tuimehng current phenomena 25 and wave nature of microscopic particles (cf. Table 1) finally resulted in the portentous night of 16 March, 1981,... [Pg.306]

The conventional conceptual content of quantum mechanics was initiated by the Copenhagen School when it was recognized that one could express the linear Schrodinger wave mechanics [28] in terms of a probability calculus, whose solutions are represented with a Hilbert function space. Max Bom then interpreted the wave nature of matter in terms of a spatially distributed probability amplitude—a wave represented by a complex function—to accompany the material particle as it moves from one place to another. The Copenhagen view was then to define the basic nature of matter in terms of the measurement process, with an underlying probability calculus, wherein the probability densities (for locating the particles of matter/volume) are the real-number-valued moduli of the matter wave amplitudes. [Pg.702]


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See also in sourсe #XX -- [ Pg.60 ]




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