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Decomposition spectral

We restrict ourselves to finite-dimensional Hilbert spaces, making H a Her-mitian matrix. We denote the eigenvalues of H q) by Efc(g) and consider the spectral decomposition... [Pg.386]

Fig. 2. The BO model is the adiabatic limit of full QD if energy level crossings do not appear. QCMD is connected to QD by the semiclassical approach if no caustics are present. Its adiabatic limit is again the BO solution, this time if the Hamiltonian H is smoothly diagonalizable. Thus, QCMD may be justified indirectly by the adiabatic limit excluding energy level crossings and other discontinuities of the spectral decomposition. Fig. 2. The BO model is the adiabatic limit of full QD if energy level crossings do not appear. QCMD is connected to QD by the semiclassical approach if no caustics are present. Its adiabatic limit is again the BO solution, this time if the Hamiltonian H is smoothly diagonalizable. Thus, QCMD may be justified indirectly by the adiabatic limit excluding energy level crossings and other discontinuities of the spectral decomposition.
Altogether, the three different models discussed so far are interconnected as sketched in Fig. 2. Now, we can by-pass the problems connected to caustics For e being small enough QCMD is justified as an approximation of QD if we exclude energy level crossings and discontinuities of the spectral decomposition. [Pg.388]

An important property of the time autocorrelation function CaU) is that by taking its Fourier transform, F CA(t) a, one gets a spectral decomposition of all the frequencies that contribute to the motion. For example, consider the motion of a single particle in a hannonic potential (harmonic oscillator). The time series describing the position of the... [Pg.54]

ME Ochs, RS Stoyanova, E Arias-Mendoza, TR Brown. A new method for spectral decomposition using a bilinear Bayesian approach. I Magn Reson 137 161-176, 1999. [Pg.345]

In order to compute the second eigenvector, we make use of the spectral decomposition of the matrix A ... [Pg.35]

The spectral decomposition of a symmetric matrix A can be rewritten in the form ... [Pg.38]

The spectral decomposition can also be used to compute various powers of a symmetric matrix. For example, the square of a symmetric matrix A of dimension p can be computed by means of its spectral decomposition ... [Pg.38]

From the spectral decomposition we can deduce that A and A always have the same rank, since the rank of a matrix is equal to the number of nonzero eigenvalues which are also the elements on the main diagonal of A (or A )-... [Pg.39]

Equation (31.3) defines the eigenvalue decomposition (EVD), also referred to as spectral decomposition, of a square symmetric matrix. The orthonormal matrices U and V are the same as those defined above with SVD, apart from the algebraic sign of the columns. As pointed out already in Section 17.6.1, the diagonal matrix can be derived from A simply by squaring the elements on the main diagonal of A. [Pg.92]

DDS(I). The signal is updated at a rate of 160 MHz. (C) The spectral decomposition of the signal. Either the fundamental wave at 20 MHz or the second-order image frequency at 180 MHz is used for the intermediate frequency. [Pg.361]

Given the nature of the Raman spectrum in the OH stretching region, and the fact that the spectral decomposition used is not unique, any set of assignments for the several components must be considered tentative. The following, based on a "common sense analysis, seems reasonable ... [Pg.148]

This result is not as satisfactory as it seems. The reader will notice that the behavior of the Gaussian components appears different from that described on p. 130. MN use the data of H. A. Lindner [Ph. D. dissertation, University of Karlsruhe (1970)], and his spectral decomposition must differ from that of Wal-rafen judging from the frequencies (see Table 2) as well as the temperature dependences of the components (see also the comments by Walrafen 30>). Until this difference is resolved, and better spectra are available, the findings of MN must be viewed with reserve. [Pg.152]

We notice that it is the analytic continuation which has the effect of breaking the time-reversal symmetry. If we contented ourselves with the continuous spectrum of eigenvalues with Re = 0, we would obtain the unitary group of time evolution valid for positive and negative times. The unitary spectral decomposition is as valid as the spectral decompositions of the forward or... [Pg.99]

Thiadiazoles are generally quite stable to heat due to the aromatic nature of the ring. Their thermal stability is influenced by the nature of the 3- and 5-substituents <65AHC(5)l 19>. Mass spectral decomposition patterns of substituted 1,2,4-thiadiazoles are discussed in Section 4.08.3.5. Photochemical behavior of 1,2,4-thiadiazoles has not been studied to date. [Pg.313]

The spectral decomposition given above for the function , enables us to obtain the following equations ... [Pg.563]

In accordance with the methodology employed while working with Cartesian coordinates, the spectral decomposition of Green s function and Dirac s distributions are both exchanged with their cylindrical coordinates in Eq. (171) written above in order to obtain the spectral component of Green s function ... [Pg.583]

We can regard Fourier transform as decomposing f into trigonometric functions of different frequencies. This spectral decomposition is based on the property... [Pg.248]

Definition of pseudo-eigenvalues. Let II be a self-adjoint operator with the spectral decomposition... [Pg.55]

Use the spectral decomposition to write A as CAC where A is the diagonal matrix of characteristic roots. Then, the Klh power of A is CAaC. Sufficiency is obvious. Also, since if some X is greater than one, Ak must explode, the condition is necessary as well. [Pg.117]

In fact, the quantized energy levels can only be detected if the time evolution of the detecting observable features quantum beats. This requires the observable to have a spectral decomposition that is concentrated on a limited number of energy levels. An example is given by the time autocorrelation of an observable D ... [Pg.511]

The classical Liouvillian operator Zc, which is the classical limit of the Landau-von Neumann superoperator in Wigner representation, can also be analyzed in terms of a spectral decomposition, such as to obtain its eigenvalues or resonances. Recent works have been devoted to this problem that show that the classical Liouvillian resonances can be obtained as the zeros of another kind of zeta function, which is of classical type. The resolvent of the classical Liouvillian can then be obtained as [60, 61]... [Pg.512]

Figure 2. Spectral decomposition of two symmetric-stretch wavepackets at (o>a/o>s) = 2.5, which is appropriate for CS2 (a) at reduced energy 0.143 and (b) at 0.286. Figure 2. Spectral decomposition of two symmetric-stretch wavepackets at (o>a/o>s) = 2.5, which is appropriate for CS2 (a) at reduced energy 0.143 and (b) at 0.286.
Selva and co-workers155 studied the mass spectral decomposition patterns of fifteen 5-aryl-3-phenyl- and four 3-aryl-5-phenyloxadiazoles and found the principal cleavage to be a retro 1,3-dipolar cycloaddition. In the latter group, the positive charge resided mainly on the 3-aryl fragment as shown by pathway la of Eq. (40) when X was varied from... [Pg.92]


See other pages where Decomposition spectral is mentioned: [Pg.387]    [Pg.15]    [Pg.41]    [Pg.34]    [Pg.321]    [Pg.226]    [Pg.137]    [Pg.28]    [Pg.138]    [Pg.140]    [Pg.142]    [Pg.150]    [Pg.231]    [Pg.162]    [Pg.117]    [Pg.216]    [Pg.192]    [Pg.562]    [Pg.33]    [Pg.34]    [Pg.598]    [Pg.615]   
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See also in sourсe #XX -- [ Pg.39 ]

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See also in sourсe #XX -- [ Pg.122 ]




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