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Quantum mechanics interactions

The development of the theory of the rate of electrode reactions (i.e. formulation of a dependence between the rate constants A a and kc and the physical parameters of the system) for the general case is a difficult quantum-mechanical problem, even when adsorption does not occur. It would be necessary to consider the vibrational spectrum of the solvation shell and its vicinity and quantum-mechanical interactions between the reacting particles and the electron at various energy levels in the electrode. [Pg.279]

Wood, R. H. Yezdimer, E. M. Sakane, S. Barriocanal, J. A. Doren, D. J., Free energies of solvation with quantum mechanical interaction energies from classical mechanical simulations, 7. Chem. Phys. 1999,110, 1329-37... [Pg.349]

As a final note, closer inspection of the emission lines from Na shows that most emission lines are not, in fact, single lines, but are closely spaced doublets or triplets - for example, the strong yellow line discussed above at 589.3 nm is composed of two separate lines at 589.0 and 589.6 nm. This is termed fine structure, and is not predictable from the Bohr model of the atom. It is addressed in the Bohr-Sommerfield model, and is the result of a quantum mechanical interaction, known as spin-orbit coupling, further discussion of which is not necessary for this volume. [Pg.285]

The Fermi contact term is often stated to be a purely quantum-mechanical interaction, having no classical analog. This is not so. The preceding derivation shows the contact interaction to be readily understandable within the framework of classical electromagnetism. [Pg.440]

Starting from the classical Heisenberg-Dirac-Van Vleck (HD W) model based on quantum mechanical interactions, all the other models can also be founded on statistical calculations. [Pg.89]

In that respect, then, the polarizable continuum estimate of hydration energy of these entities is considerably smaller than the quantum mechanical interaction energy of the molecule plus the appropriate number of first-shell water molecules. In this vein, then, it would be highly inaccurate to equate the interaction energy of a molecule such as imidazole with the molecules in its first solvation shell to the entire solvation energy when computed by a continuum approach. [Pg.426]

This failure to properly reflect the intuitive MO-population trends by the IT bond indices calls for a thorough revision of the hitherto used overall communication channel in AO resolution, which combines the contributions from all occupied MOs in the electron configuration in question. Instead, one could envisage a use of the separate MO channels introduced in Section 2 (Eq. [7b]). As an illustration, let us assume for simplicity the two-AO model of the chemical bond A-B originating from the quantum-mechanical interaction between two AOs x = ( e A, b e B). The bond contributions between this pair of AO in the information system of sth MO,... [Pg.22]

A firm result will be this if the value of the function at a given neighborhood to a point on the surface is zero, whatever you do there will never be a spectral response derived from a quantum-mechanical interaction at that neighborhood no imprint mediated by the quantum state. Another one is that any finite value different from zero of the quantum state function at a given neighborhood of a point opens a possibility for a response from a properly sensitized surface that would reflect the wavefunction at that region (Cf. Eq. (3)). [Pg.62]

In laboratory space, the state [... 0 0 0 1...] is localized at the I-frame that would act as the emission source. A detector at a given distance and position may or may not detect the energy equivalent to one quantum, yet a quantum-mechanical interaction is ensured. [Pg.99]

The Hubbard picture is the most celebrated and simplest model of the Mott insulator. It is comprised of a tight-binding Hamiltonian, written in the second quantization formalism. Second quantization is the name given to the quantum field theory procedure by which one moves from dealing with a set of particles to a field. Quantum field theory is the study of the quantum mechanical interaction of elementary particles with fields. Quantum field theory is such a notoriously difficult subject that this textbook will not attempt to go beyond the level of merely quoting equations. The Hubbard Hamiltonian is ... [Pg.289]

In solvents of moderate-to-large dielectric constant, AG °n0nei can be neglected provided there are no quantum mechanical interactions and no secondary chemical processes thus,... [Pg.236]

One of the most interesting aspects of energy transport is the excitation percolation transition (, and its similarity (10) to magnetic phase transitions and other critical phenomena (, 8). In its simplest form the problem is one of connectivity. In a binary system, made only of hosts and donors, the question is can the excitation travel from one side of the material to the other The implicit assumption is that there are excitation-transfer-bonds only between two donors that are "close enough", where "close enough" has a practical aspect (e.g. defined by the excitation transfer probability or time). Obviously, if there is a succession of excitation-bonds from one edge of the material to the other, one has "percolation", i.e. a connected chain of donors forming an excitation conduit. We note that the excitation-bonds seldom correspond to real chemical bonds rather more often they correspond to van-der-Walls type bonds and most often they correspond to a dipole-dipole or equivalent quantum-mechanical interaction. [Pg.59]

A few of the characteristics of the integrals that need to be solved in the secular determinant should be outlined. Haa and Hbb are called coulomb integrals and are described as the energy of an electron occupying the basis orbital A or B. The resonance integral, Hab, is the quantum mechanical interaction term of basis orbital A with basis orbital B. 5ab is the overlap integral, the quantitative measure of the volume in space where the two basis functions interact. Basis functions that have zero overlap are said to be mutually orthogonal while two functions that are exactly coincident have an overlap value equal to 1 Saa = Sbb = 1, hence the simplification in the secular determinant above). In the secular determinant for the H2+ system or any homonuclear diatomic system, Haa = Hbb-... [Pg.2732]

Quantum Mechanical Interaction Potentials for Weak Interactions. - Development of quantum mechanical intermolecular potentials is challenging because of the weakness of the interactions, and because the dominant forces are often dispersion forces which are much more difficult to determine accurately than other interactions such as electrostatic interactions. [Pg.334]

Radiation damping No collisions or or quantum mechanical interactions uncertainty (natural line width)... [Pg.320]

Once the rotational spectrum of a molecule is obtained, it must be analyzed. Such an analysis insures that the transitions observed correspond to the correct energy level differences. The data is fit to a molecular model, the so-called effective Hamiltonian , which describes the quantum mechanical interactions in a given species, and spectroscopic constants are obtained. As mentioned, these constants can be used to predict rotational transitions that could not be measured. Naturally, the model must be extremely accurate for the constants to have predictive power to 1 part in 10 or 10 , A typical Hamiltonian for a radical species might be ... [Pg.121]

The macroscopically observed transport is based on the quantum-mechanical interaction between the electron waves in neighbouring quantum metal particles , which is probably facilitated by the Maxwell-Wagner polarisation and thermally stimulated. Instead of hopping , the expression tunnelling may approximate more closely to the quantum mechanical fundamentals of this process. [Pg.618]

The density functional theorem states that exists but provides no way to derive its explicit form. In particular, there is no explicit equation for the exchange/correlation term, v c, which embodies all the difficult quantum mechanical interactions between the particles in the system. We are forced... [Pg.39]


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