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Non-relativistic quantum mechanics

In the non-relativistic quantum mechanics discussed in this chapter, spin does not appear naturally. Although... [Pg.28]

A marvellous and rigorous treatment of non-relativistic quantum mechanics. Although best suited for readers with a fair degree of mathematical sophistication and a desire to understand the subject in great depth, the book contains all of the important ideas of the subject and many of the subtle details that are often missing from less advanced treatments. Unusual for a book of its type, highly detailed solutions are given for many illustrative example problems. [Pg.52]

The central equation of (non-relativistic) quantum mechanics, governing an isolated atom or molecule, is the time-dependent Schrodinger equation (TDSE) ... [Pg.226]

The aim of this section is to show how the modulus-phase formulation, which is the keytone of our chapter, leads very directly to the equation of continuity and to the Hamilton-Jacobi equation. These equations have formed the basic building blocks in Bohm s formulation of non-relativistic quantum mechanics [318]. We begin with the nonrelativistic case, for which the simplicity of the derivation has... [Pg.158]

Bas, A.I., Ya.B. Zeldovich and A.M. Perelomov, 1971, Scattering Reactions and Decays in the Non-relativistic Quantum Mechanics (Nauka, Moscow [in Russian)]. [Pg.140]

There is a nice point as to what we mean by the experimental energy. All the calculations so far have been based on non-relativistic quantum mechanics. A measure of the importance of relativistic effects for a given atom is afforded by its spin-orbit coupling parameter. This parameter can be easily determined from spectroscopic studies, and it is certainly not zero for first-row atoms. We should strictly compare the HF limit to an experimental energy that refers to a non-relativistic molecule. This is a moot point we can neither calculate molecular energies at the HF limit, nor can we easily make measurements that allow for these relativistic effects. [Pg.187]

Prior to Dirac s relativistic quantum theory, W. Pauli (1927) showed how spin could be incorporated into non-relativistic quantum mechanics. Since the subject of relativistic quantum mechanics is beyond the scope of this book, we present in this chapter Pauli s modification of the wave-function description so... [Pg.195]

The relationship between spin and the symmetry character of the wave function can be established in relativistic quantum theory. In non-relativistic quantum mechanics, however, this relationship must be regarded as a postulate. [Pg.217]

Solution of (12) gives the complete non-relativistic quantum-mechanical description of the hydrogen atom in its stationary states. The wave function is interpreted in terms of... [Pg.346]

From the perspective of non-relativistic quantum mechanics, a collection of electrons and atomic nuclei interact through the Coulomb Hamiltonian... [Pg.107]

Calculations using the methods of non-relativistic quantum mechanics have now advanced to the point at which they can provide quantitative predictions of the structure and properties of atoms, their ions, molecules, and solids containing atoms from the first two rows of the Periodical Table. However, there is much evidence that relativistic effects grow in importance with the increase of atomic number, and the competition between relativistic and correlation effects dominates over the properties of materials from the first transition row onwards. This makes it obligatory to use methods based on relativistic quantum mechanics if one wishes to obtain even qualitatively realistic descriptions of the properties of systems containing heavy elements. Many of these dominate in materials being considered as new high-temperature superconductors. [Pg.10]

Ya.B. s contribution to the theory of unstable states is systematized in his monograph Scattering, Reactions and Fission in Non-Relativistic Quantum Mechanics [14], and one of his papers will be included in the book Particles, Nuclei, and the Universe. [Pg.17]

A. I. Baz , B. Ya. Zel dovich, A. M. Perelomov, Scattering, Reactions Decays in Non-Relativistic Quantum Mechanics, Nauka, Moscow, 1971. [Pg.64]

In the non-relativistic quantum mechanics the nuclear recoil effect for a hydrogenlike atom is easily taken into account by using the reduced mass p = mM/(m + M) instead of the electron mass m (M is the nuclear mass). It means that to account for the nuclear recoil effect to first order in m/M we must simply replace the binding energy E by E(1 — m/M). [Pg.714]

Schrodinger, Heisenberg. Non-relativistic quantum mechanics. Wave equation yields Bohr energy levels. [Pg.817]

Atomic units are used in all equations and all considerations concern non-relativistic quantum mechanics in Born-Oppenheimer approximation. Square brackets, as in E[p] for instance, are used to indicate that the relevant quantity is a functional i.e. the correspondence between a function in real space p = p(r) and a real number (energy in this example). Abbreviations or acronyms denoting different approximate exchange-correlation functionals reflect their common usage in the literature. They are collected in Appendix. Unless specified, the equations are given for the spin-compensated case. [Pg.157]

Feynman, R.P. (1948). Space-time approach to non-relativistic quantum mechanics. Rev. Mod. Phys. 20, 367-387. [Pg.302]

The traditional methods of solution of many of the soluble problems of non-relativistic quantum mechanics employ a wide variety of analytical and algebraic methods, and their closed-form eigensolutions are usually expressed in terms of many different higher mathematical functions. However, most of these diverse functions can also be expressed quite conveniently in terms... [Pg.173]

The model used in these considerations is liighly simplified only one particle is assumed to move, the other constituents of the nucleus not being considered separately, but only as the sources of the force acting on the moving particle. Recently various attempts have been made to treat the nucleus a,s a system of many particles with the help of the methods of non-relativistic quantum mechanics. For this purpose definite assumptions about the forces between the elementary particles (neutrons and protons) are necessary. It then becomes pos-... [Pg.183]

During the second half of the last century chemistry revealed a large number of systems, whose theoretical description requires an extension of the framework of non-relativistic quantum mechanics. For example, the spectral properties and binding energies of heavy element compounds and transition-metal complexes are governed by relativistic effects. Many experimental results for... [Pg.622]

While the Hartree system is appropriate fore the discussion of relativistic effects, because the limit o —> 0 ( or c —> oo) corresponds to non-relativistic quantum mechanics, in the natural system the limit a — 0 (or —> 0)... [Pg.669]

In the case of one particle QO, the necessary quadrivector structure, which must adopt the extended wavefunctions, acquire a qualitative similarity to relativistic spinors [77]. In order to obtain mathematics coherence, even non-relativistic Quantum Mechanics seems that can be easily attached to a vector-like wavefunction representation, originated due to the presence of momentum and thus of KE differential operators. An idea of Levy-Leblond [78], recently quoted by Karbowski [79] can be related to this feature. [Pg.17]


See other pages where Non-relativistic quantum mechanics is mentioned: [Pg.254]    [Pg.54]    [Pg.61]    [Pg.9]    [Pg.85]    [Pg.291]    [Pg.36]    [Pg.179]    [Pg.245]    [Pg.209]    [Pg.210]    [Pg.7]   


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