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Electric field interactions

It turns out that there is another branch of mathematics, closely related to tire calculus of variations, although historically the two fields grew up somewhat separately, known as optimal control theory (OCT). Although the boundary between these two fields is somewhat blurred, in practice one may view optimal control theory as the application of the calculus of variations to problems with differential equation constraints. OCT is used in chemical, electrical, and aeronautical engineering where the differential equation constraints may be chemical kinetic equations, electrical circuit equations, the Navier-Stokes equations for air flow, or Newton s equations. In our case, the differential equation constraint is the TDSE in the presence of the control, which is the electric field interacting with the dipole (pemianent or transition dipole moment) of the molecule [53, 54, 55 and 56]. From the point of view of control theory, this application presents many new features relative to conventional applications perhaps most interesting mathematically is the admission of a complex state variable and a complex control conceptually, the application of control teclmiques to steer the microscopic equations of motion is both a novel and potentially very important new direction. [Pg.268]

This situation appears to be different when microwave conductivity measurements are used in parallel with electrochemical measurements. As Fig. 1 shows, there is a marked parallelism between electrochemical processes and microwave conductivity mechanisms. In both cases electrical fields interact with electronic or ionic charge carriers as well as dipoles. In electrochemical processes, it is a static or low-frequency electrical field that is moving electrical charge carriers or orienting dipoles. In a micro-wave measurement, the electric field of the microwave interacts with... [Pg.436]

Usually we call neutral molecule as polar one if it has considerable permanent electric dipole moment /i°. The total dipole moment should include also an induced one, aR (a is a polarizability of the molecule, R is the intensity of electric field interacting with molecule), and may be presen ted as /i = /<° + a . Permanent part of dipole moment for nonsymmetrical organic molecules usually accepted to be essentially larger than induced one that is why orientational forces or interactions of permanent electric dipoles are the most important in polar solutions [1,2,4,12, 39]. [Pg.207]

The situation becomes even worse when the Boltzmann formula is used to interpret the absorption of radiant energy by molecules. Electromagnetic radiation considered as a fluctuating electric field interacts with electrons in... [Pg.265]

In contrast to this, with a homogeneous membrane corresponding to Problem 3, the motion in a symmetry cell of the liquid boundary layer, adjacent to an electrically inhomogeneous membrane, is induced by the electric field interaction with an essentially nonequilibrium space charge, formed only in the course of the ionic transport itself. [Pg.248]

If the system is in the presence of a radiation field, then Hs in Eq. (5.12) is augmented by the dipole-electric field interaction HUR [Eq. (2.10)]. The result is the so-called optical Bloch equations. Note that this approach focuses explicitly on decoherence in the energy representation. [Pg.99]

The apphed electric field interacts with the electric dipole moment of the molecule nuclear spin is not involved in the decoupled basis set, so that we need only the results of our earlier analysis, given in equation (8.278), i.e. [Pg.479]

The reason that chemical laws are not simply reduced to electrostatics is that the electrons behave under the influence of their own or applied electric fields, not according to classical mechanics, but according to quantum mechanics obeying the singular Pauli principle. In fact, electrostatics and dielectric constants are simpler applications of the electrical structure of molecules and use outside macroscopic homogeneous electric fields interacting with microscopic inhomogeneous fields. [Pg.99]

A volume of charged, current-containing matter, such as an atomic nucleus, interacts with the electromagnetic field. The electric field interacts with only the nuclear charge distribution, while the magnetic field interacts with the nuclear current distribution. The interaction energy, H%, between the electric field and the nuclear charge may be written as... [Pg.215]

Another mode of protein-electric field interaction has been proposed by Blank (18-21). Blank considers that the effects of an electric field on membrane protein mainly arise from its effect on the electric double layer at the water-membrane interface. In other words, an electric field can change the concentration of ions near a membrane protein, which results in a stimulation or a reduction in its activity. The surface compartmental model has been used to interpret the ac stimulated adenosine triphosphate (ATP) splitting of Na, K-ATPase (adenosine triphosphatase) and ribonucleic acid (RNA) synthesis in various types of cells (19-21). [Pg.554]

Fig. 17.26 The temperature dependence of the quadrupole splitting of the Tm resonance in thulium metal. The solid line represents a theoretical curve derived from the crystalline electric field interactions. [Ref. 166, Fig. 1]... Fig. 17.26 The temperature dependence of the quadrupole splitting of the Tm resonance in thulium metal. The solid line represents a theoretical curve derived from the crystalline electric field interactions. [Ref. 166, Fig. 1]...
An applied electric field ( ) interacts with the electric dipole moment (fx ) of a polar diatomic molecule, which lies along the direction of the intemuclear axis. The applied field defines the space-fixed p = 0 direction, or Z direction, whilst the molecule-fixed = 0 direction corresponds to the intemuclear axis. Transformation from one axis system to the other is accomplished by means of a first-rank rotation matrix, so that the interaction may be represented by the effective Hamiltonian as follows ... [Pg.465]


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See also in sourсe #XX -- [ Pg.3 ]




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