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Wave equation including the time

Let us consider an unperturbed system with wave equation including the time... [Pg.294]

Insertion of (4.9) into the time-dependent wave equation, including the time-dependent perturbation V t) described in the introduction of section 4.2, enables one to deduce the absorption rate... [Pg.133]

The description of the unperturbed system is given by the wave equation including time... [Pg.55]

The radial wave function has (n — l+l) nodes, where n and l are the quantum numbers. To solve the radial atomic wave equation above, the Herman-Skillman method [12] is usually used. The equation above may be rewritten in a logarithmic coordinate of radius. The radial wave equation is first expressed in terms of low-power polynomials near the origin at the nucleus [13]. With the help of the derived polynomials near the origin, the equation is then numerically solved step by step outward from the origin to satisfy the required node number. At the same time, the radial wave equation is solved numerically from a point far away from the origin, where the radial wave function decays exponentially. The inner and outer solutions are required to be connected smoothly including derivative at a connecting point. [Pg.51]

It may seem reasonable that the MO method gives a result that underestimates the bond dissociation energy because the wave equation includes patterns of electron density that resemble ionic species such as a b . But why is the VB result also in error The answer seems to be that, while the MO approach places too much emphasis on these ionic electron distributions, the VB approach underutilizes them. A strong bond apparently requires that both electrons spend a lot of time in the region of space between the two protons. Doing so must make it more likely that the two electrons will, at some instant, be on the same atom. Thus, we might improve the accuracy of the VB calculation if we add some terms that keep the electrons closer together between the nuclei. [Pg.26]

Schrodinger also wrote down a wave equation that includes time and may be regarded as the wave equation that replaces classical equations of motion. That equation is referred to as the wave equation or the Schrodinger equation. To solve the wave equation (see Chapter 5), we use the solutions of the time-independent equation. With boundary conditions, we obtain the motion of the wave packet. [Pg.12]

Applying the time-dependent perturbation is straigthforward and leads to LR-CC methods. The nonlinear systems of equations include the normal T and Ti (for CCSD) operators-amplitudes and additionally single and double excitation (time-dependent) response amplitudes (for details the reader is referred to Refs. 1, 64, 88, 89 and references cited therein). An alternative approach, that, although conceptually different yields exactly the same excitation energies, is the equation-of-motion coupled cluster (EOM-CC) method [90]. The EOM-CC equations also contain the CC wave function 4 cc) (Eq. [50]) and a second (state-dependent) excitation operator R including single, double,. .. excitations (usually R is truncated in the same manner as T). The EOM equations read as... [Pg.185]

Whether EM radiation or particles ate cf interest fcr scattering, the solution to the Helmholtz equation has the same form. Including the time dependent portion, this solution is E(r,t)=Eoexp i(k r-mt] for the electric field component of the wave. This is the equation ofa plane wave with amplitude Eo, characterized at a given instant in time by smfaces of constant phase which are planes (i.e, for which k inconstant). [Pg.3]

In the DC-biased structures considered here, the dynamics are dominated by electronic states in the conduction band [1]. A simplified version of the theory assumes that the excitation occurs only at zone center. This reduces the problem to an n-level system (where n is approximately equal to the number of wells in the structure), which can be solved using conventional first-order perturbation theory and wave-packet methods. A more advanced version of the theory includes all of the hole states and electron states subsumed by the bandwidth of the excitation laser, as well as the perpendicular k states. In this case, a density-matrix picture must be used, which requires a solution of the time-dependent Liouville equation. Substituting the Hamiltonian into the Liouville equation leads to a modified version of the optical Bloch equations [13,15]. These equations can be solved readily, if the k states are not coupled (i.e., in the absence of Coulomb interactions). [Pg.251]

Various difficulties of classical physics, including inadequate description of atoms and molecules, led to new ways of visualizing physical realities, ways which are embodied in the methods of quantum mechanics. Quantum mechanics is based on the description of particle motion by a wave function, satisfying the Schrodinger equation, which in its time-independent form is ... [Pg.3]

Technically, the time-independent Schrodinger equation (2) is solved for clamped nuclei. The Hamiltonian is broken into its electronic part, He, including the nuclear Coulomb repulsion energy, and the nuclear Hamiltonian HN. At this level, mass polarization effects are usually neglected. The wave function is therefore factorized as usual (r,X)= vP(r X)g(X). Formally, the electronic wave function d lnX) and total electronic energy, E(X), are obtained after solving the equation for each value of X ... [Pg.286]

The second part of the work involves implementing a robust controller. The key issue in the controller design is the treatment of system dynamics uncertainties and rejection of exogenous disturbances, while optimizing the flow responses and control inputs. Parameter uncertainties in the wave equation and time delays associated with the distributed control process are formally included. Finally, a series of numerical simulations of the entire system are carried out to examine the performance of the proposed controller design. The relationships among the uncertainty bound of system dynamics, the response of flow oscillation, and controller performance are investigated systematically. [Pg.357]

The surface-hopping trajectories obtained in the adiabatic representation of the QCLE contain nonadiabatic transitions between potential surfaces including both single adiabatic potential surfaces and the mean of two adiabatic surfaces. This picture is qualitatively different from surface-hopping schemes [2,56] which make the ansatz that classical coordinates follow some trajectory, R(t), while the quantum subsystem wave function, expanded in the adiabatic basis, is evolved according to the time dependent Schrodinger equation. The potential surfaces that the classical trajectories evolve along correspond to one of the adiabatic surfaces used in the expansion of the subsystem wavefunction, while the subsystem evolution is carried out coherently and may develop into linear combinations of these states. In such schemes, the environment does not experience the force associated with the true quantum state of the subsystem and decoherence by the environment is not automatically taken into account. Nonetheless, these methods have provided com-... [Pg.399]


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See also in sourсe #XX -- [ Pg.53 , Pg.85 ]




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