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Energy quantized level

These are the same quantized energy levels that arose when the wavefunetion boundary eonditions were matehed at x = 0, x = Lx and y = 0, y = Ly. In this ease, one says that the Bohr-Sommerfeld quantization eondition ... [Pg.20]

This technique for finding a weighted average is used for ideal gas properties and quantum mechanical systems with quantized energy levels. It is not a convenient way to design computer simulations for real gas or condensed-phase... [Pg.13]

For reactions between atoms, the computation needs to model only the translational energy of impact. For molecular reactions, there are internal energies to be included in the calculation. These internal energies are vibrational and rotational motions, which have quantized energy levels. Even with these corrections included, rate constant calculations tend to lose accuracy as the complexity of the molecular system and reaction mechanism increases. [Pg.167]

Quasiclassical calculations are similar to classical trajectory calculations with the addition of terms to account for quantum effects. The inclusion of tunneling and quantized energy levels improves the accuracy of results for light atoms, such as hydrogen transfer, and lower-temperature reactions. [Pg.168]

Four types of transitions between quantized energy levels account for molecular UV/Vis spectra. The approximate wavelength ranges for these absorptions, as well as a partial list of bonds, functional groups, or molecules that give rise to these transitions is shown in Table 10.5. Of these transitions, the most important are the n and TZ —> TZ, because they involve functional groups that are characteristic... [Pg.382]

Translational energy, which may be directly calculated from the classical kinetic theory of gases since the spacings of these quantized energy levels are so small as to be negligible. The Maxwell-Boltzmann disuibution for die kinetic energies of molecules in a gas, which is based on die assumption diat die velocity specuum is continuous is, in differential form. [Pg.43]

On the other hand, even in particle systems the coulomb blockade (Van Bentum et al. 1988a) and the coulomb staircase (Van Bentum et al. 1988b) were observed, some nonlinear effects were observed in the current-voltage characteristics (Wilkins et al. 1989), and behavior related to the quantized energy levels inside the particles was described (Crom-mie et al. 1993, Dubois et al. 1996). [Pg.175]

The emission spectra of He and reveal transitions at characteristic energies. The emitted photons have different wavelengths and energies because iHe has quantized energy levels that are different from those of l ... [Pg.503]

Solving equation (6.21) for the energy E and replacing A by n, we obtain the quantized energy levels for the hydrogen-like atom... [Pg.168]

The model of metal-ammonia solutions that has emerged is based on ionization of the metal atoms to produce metal ions and electrons that are both solvated. The solvated electron is believed to reside in a cavity in ammonia, and thus it may behave as a particle in a three-dimensional box with quantized energy levels. Transitions between the energy levels may give rise to absorption of light and thereby cause the solutions to be colored. The dissolution process can be represented as... [Pg.341]

In fact, electron transfer occurs at the microscopic level where quantum mechanics provides the necessary description of the phenomenon (5-13). In the quantum mechanical solution, associated with the potential curves in Figure 1 are quantized energy levels, Ej = (vj + 1/2) 100., where Vj and 2ttvj are the vibrational... [Pg.156]

Figure 10.9. (a) Schematic structure of a silicon quantum dot crystal and (b) its calculated electronic structure as a function of interparticle distance H. The size of the nanoparticles is L = 6.5 nm. At small H, a splitting of the quantized energy levels of single dots results in the formation of three-dimensional minibands. Reproduced from Ref. 64, Copyright 2001, with permission from the American Institute of Physics. [Pg.324]

The behaviour of electrons in metals shows the translational properties of quantum particles having quantized energy levels. These cannot be approximated to the continuous distribution describing particles in a gas because of the much smaller mass of the electron when compared with atoms. If one gram-atom of a metal is contained in a cube of length L, the valence electrons have quantum wavelengths, X, described by the de Broglie equation... [Pg.150]

The concept of discrete or quantized energy levels can be superimposed on this diagram by representing them as a series of horizontal lines, the spacing of which becomes closer with increasing energy due to the anharmonic nature of the vibration. In quantum mechanical terms, these levels are labelled V =... [Pg.379]

In contrast to ESR spectroscopy, which can only be used to study species with unpaired electrons, NMR spectroscopy is applicable to the investigation of all polymer samples. Nuclei with non-zero total nuclear spin (e.g., 1H, l3C, 19F, 14N) will have a magnetic moment which will interact with an external magnetic field resulting in quantized energy levels. Transitions between these energy levels form the basis of NMR spectroscopy. 1H and 13C... [Pg.38]

Abstract Silver clusters, composed of only a few silver atoms, have remarkable optical properties based on electronic transitions between quantized energy levels. They have large absorption coefficients and fluorescence quantum yields, in common with conventional fluorescent markers. But importantly, silver clusters have an attractive set of features, including subnanometer size, nontoxicity and photostability, which makes them competitive as fluorescent markers compared with organic dye molecules and semiconductor quantum dots. In this chapter, we review the synthesis and properties of fluorescent silver clusters, and their application as bio-labels and molecular sensors. Silver clusters may have a bright future as luminescent probes for labeling and sensing applications. [Pg.307]

A clear, commonly accepted terminology to describe few-atom subnanoscale metals exhibiting quantized energy levels is lacking. The lack of a coherent terminology leads to confusion and may hamper development. In this chapter, we restrict the term metal cluster to describe few-atom metals with discrete energy levels, and use metal nanoparticle, for particles that have surface plasmon resonance effects (approximate size range between 1 and 100 nm). [Pg.310]

Bohr s Equation If we consider two quantized energy levels e.g., higher as E2 and lower as Ex, the radiation given out during the transition from E2 to E, may be expressed by the following equation ... [Pg.371]

The discrete energy levels sketched as horizontal lines on each potential curve of Figure 5.10 are consistent with the quantized energy levels (phonon levels) of a harmonic oscillator. For each harmonic oscillator at frequency 12, the permitted phonon energies are given by... [Pg.174]

The colour of a chromophore depends on the way its valence-shell electrons interact with light, i.e. its colour depends on the way it absorbs photons. Photons are absorbed during the promotion of an electron between wave-mechanically allowed (i.e. quantized) energy levels. The magnitude of the energy required to achieve this, E, is given by the Planck equation, as follows ... [Pg.240]

There are two effects of the anharmonicity of the quantized energy levels described above, which have signiflcance for NIRS. First, the gap between adjacent energy levels is no longer constant, as it was in the simple harmonic case. The energy levels converge as n increases. Second, the rigorous selection rule that An = +1 is relaxed, so that weak absorptions can occur with n = 2 (flrst overtone band), or +3 (second overtone band), etc. [Pg.113]

Figure 3.2 shows the experimental potential well for the H2 molecule, compared with the harmonic fit and the Morse potential. Horizontal lines represent quantized energy levels. Note that, as vibrational quantum number n increases, the energy gap between neighboring levels diminishes and the equilibrium distance increases, due to the anharmonicity of the potential well. The latter fact is responsible for the thermal expansion of the substance. [Pg.127]


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