0 electrodynamics effect

It is a prominent problem whether a negative quark can be transferred from one atom to another. If the low radii of quark 1 s orbitals are considered, the exceedingly low overlap integrals (16) would not permit transfer in times far in excess of 1010 years, unless some higher-order electrodynamic effect is of assistance. Already the motion of a F 1 s hole between two adjacent fluorine atoms in a molecule (36) takes more than 10-8 sec, i.e., many million times the lifetime of the ionized system... 

Giessmann, U. Rollgen, F.W. Electrodynamic Effects in Field Desorption Mass Spectrometry. Int. J. Mass Spectrom. Ion Phys. 1981, 38, 267-279. 

Quantum electrodynamics effects (see [29] and section 2.3), arbitrary nuclear models, and correlation with IC shells [30] can be efficiently treated within GRECPs. 

When innermost core shells must be treated explicitly, the four-component versions of the GREGP operator can be used, in principle, together with the all-electron relativistic Hamiltonians. The GRECP can describe here some quantum electrodynamics effects (self-energy, vacuum polarization etc.) thus avoiding their direct treatment. One more remark is that the... 

The data of atomic spectroscopy are of extreme importance in revealing the nature of quantum-electrodynamical effects. For the investigation of many-electron atoms and ions, it is of great importance to combine theoretical and experimental methods. Therefore, the methods used must be universal and accurate. A number of physical characteristics of the many-electron atom (e.g., a complete set of quantum numbers) may be found only on the basis of theoretical considerations. In many cases the mathematical modelling of physical objects and processes using modern computers may successfully replace the corresponding experiments. In this book we shall describe the contemporary state of the theory of many-electron atoms and ions, the peculiarities of their structure and spectra as well as the processes of their interaction with radiation, and some applications. 

The interpretation of Eq. (584) is that the potential A(3) is defined along the integration path of the line integral. The field Ba> is defined as being perpendicular to the plane or surface enclosed by the line integral. Neither A(3) nor B<3) exists in a U(l) invariant electrodynamics. Effects attributed to the topological... 

All the terms up to this point can be calculated to high precision, leaving a finite residual piece due to higher order relativistic and quantum electrodynamic effects which lie at the frontier of current theory. 

The difference in the energy of the 2 Sand 2 Pjy2 levels in hydrogenic atoms is a purely electrodynamic effect due to the interaction of the bound electron with the quantized electromagnetic field. The measurement of this splitting was a major stimulus for the development of renormalization theory and still provides an important test of Quantum Electrodynamics. The precise measurement of this split-ting is difficult because of the short radiative lifetime of the 2 P 2 state. 

Aside from relativistic and quantum electrodynamic effects, a single molecule in free space is completely described by the Schrfidinger equation (8-2.1)... 

A detailed theoretical treatment based on both electrostatic and electrodynamic effects of an optical electric field on a metal particle is beyond the scope of this chapter, but such approaches have been discussed extensively (1,5-7). Several of the main theoretical points are of value to analytical applications and will be summarized here. 

S. Mikhailov, Microwave-induced magnetoransport phenomena in two-dimensional electron system Importance of electrodynamic effects, Phys. Rev. B 70, 165311 (2004). 

The theoretical energy levels are determined to high accuracy by the Dirac eigenvalue, quantum electrodynamic effects such as the self energy and vacuum polarization, finite-nuclear-size corrections, and nuclear motion effects. 

In this last section we mention a few cases, where properties other than the energy of a system are considered, which are influenced in particular by the change from the point-like nucleus case (PNC) to the finite nucleus case (FNC) for the nuclear model. Firstly, we consider the electron-nuclear contact term (Darwin term), and turn then to higher quantum electrodynamic effects. In both cases the nuclear charge density distribution p r) is involved. The next item, parity non-conservation due to neutral weak interaction between electrons and nuclei, involves the nuclear proton and neutron density distributions, i.e., the particle density ditributions n r) and n (r). Finally, higher nuclear electric multipole moments, which involve the charge density distribution p r) again, are mentioned briefly. 

The leading quantum electrodynamic effects to be accounted for in electronic structure calculations are the radiative corrections known as electron self-energy interaction and vacuum polarization. For the energy of electronic systems, the latter is usually small compared to the former, but only the latter can be expressed in terms of an effective additive potential to be included in the electronic structure calculations. The total vacuum polarization potential can be expanded into a double power series in the fine structure constant a and the external coupling constant Za. The lowest-order term, the Uehling potential, can be expressed as [110-112] ... 

In his work, Goldstone70 introduced the graphical techniques into many-body physics making use of Feynman-like diagrams. However, interactions were taken to be instantaneous and the effects of relativity were ignored. In recent years, the growing interest in the treatment of relativistic and quantum electrodynamic effects in atoms and molecules is necessitating the reintroduc-... 

If one were to hazard a guess as to where the major new developments in quantum chemistry will be in the next fifteen years, the proper treatment of relativity and the introduction of quantum electrodynamic effects seem to us to be likely candidates ... 

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