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Complex similarity transformations

So far, we have included in the definition space A = F only complex functions F = F(X) of the real compositive variable X = xt, x2,..., xN. We will now extend this space by also including complex functions F = F(Z) of a composite complex variable Z = zx, z2,..., zN, and we will introduce such functions essentially through complex similarity transformations. [Pg.103]

The unitary transform does the same thing as a similarity transform, except that it operates in a complex space rather than a real space. Thinking in terms of an added imaginary dimension for each real dimension, the space of the unitary matrix is a 2m-dimensionaI space. The unitary transform is introduced here because atomic or molecular wave functions may be complex. [Pg.44]

The first report on the Pd(II)-promoted Cope rearrangement is the conversion of fw./ra/w-l,5-cyclodecadiene (44) into c/5-l,2-divinylcyclohexane-PdCl2 complex (45) with a stoichiometric amount of PdCl2(PhCN)2 at room temperature. The complex formation is the driving force of this unusual rearrangement [38,39]. A similar transformation of germacrane (l,5-dimethyl-8-isopropyli-dene-/rfflu,/ra j-l,5-cyclodecadiene) takes place[40j. [Pg.533]

The fuels consumed in the fire were treated wood, penta, and creosote (coal tars). Both are considered combustible liquids, with flash points above 160° F (CC). Vapor conditions within the headspaces of tanks can, however, reach explosive conditions, and the introduction of an ignition source resulted in spontaneous combustion. Under ideal conditions, creosote burns similar to crude oil, and in standard lab burn tests, has an average burn rate of 4 mm/min. There is no data on the burn rate of penta however, its vapors would have likely burned at much slower rates and a series of complex chemical transformations would have occurred. [Pg.338]

Similar transformations have been performed with Danishefsky s diene and glyoxylate esters [85] catalyzed by bis (oxazoHne)-metal complexes to afford the hetero Diels-Alder product in 70% isolated yield and up to 72% ee. Jorgensen [86,87] reported a highly enantioselective, catalytic hetero Diels-Alder reaction of ketones and similar chiral copper(II) complexes leading to enantiomeric excesses up to 99% (Scheme 31, reaction 2). They also described [88] a highly diastereo- and enantioselective catalytic hetero Diels-Alder reaction of /I, y-imsaturated a-ketoesters with electron-rich alkenes... [Pg.118]

The gas motion near a disk spinning in an unconfined space in the absence of buoyancy, can be described in terms of a similar solution. Of course, the disk in a real reactor is confined, and since the disk is heated buoyancy can play a large role. However, it is possible to operate the reactor in ways that minimize the effects of buoyancy and confinement. In these regimes the species and temperature gradients normal to the surface are the same everywhere on the disk. From a physical point of view, this property leads to uniform deposition - an important objective in CVD reactors. From a mathematical point of view, this property leads to the similarity transformation that reduces a complex three-dimensional swirling flow to a relatively simple two-point boundary value problem. Once in boundary-value problem form, the computational models can readily incorporate complex chemical kinetics and molecular transport models. [Pg.335]

Unlike the case of the Ni-catalyzed reaction, which afforded the branched thioester (Eq. 7.1), the PdCl2(PPh3)3/SnCl2-catalyzed reaction with 1-alkyne and 1-alkene predominantly provided terminal thioester 6 in up to 61% yield in preference to 7. In 1983, a similar hydrothiocarboxylation of an alkene was also documented by using a Pd(OAc)2/P( -Pr)3 catalyst system with t-BuSH to form 8 in up to 79% yield (Eq. 7.6) [16]. It was mentioned in the patent that the Pt-complex also possessed catalyhc activity for the transformation, although the yield of product was unsatisfactory. In 1984, the hydrothiocarboxylation of a 1,3-diene catalyzed by Co2(CO)g in pyridine was also reported in a patent [17]. In 1986, Alper et al. reported that a similar transformation to the one shown in Eq. (7.3) can be realized under much milder reaction conditions in the presence of a 1,3-diene [18], and the carboxylic ester 10 was produced using an aqueous alcohol as solvent (Eq. 7.7) [19]. [Pg.219]

Oxidative addition of dihydrogen commonly involves transformation of a d8 square planar metal complex into a d6 octahedral metal complex, or similar transformations involving d2 — d°, d10 —> d8 etc. The oxidative addition of... [Pg.48]

In a quest for a more environment-friendly process it has been found that reaction 8.4 can be catalyzed by Pd(II) complexes of various nitrogen-donor ligands (Scheme 8.1) under not too harsh conditions (100 °C, air) without the need of copper chlorides [10,11]. Of the investigated ligands, sulfonated batophenanthroline proved to be the best. Higher olefins, such as 1-hexene or cyclooctene were similarly transformed by this catalyst. Very importantly, there was no isomerization to internal olefins and 2-hexanone was formed with higher than 99 % selectivity. This outstanding selectivity is probably due to the absence of acid and Cu-chlorides. [Pg.212]

In a similar way, a novel route for synthesis of cr,/ -unsaturated amide 242 is explored via intermolecular coupling of four components, that is, alkyne, hydrosilane, amine, and GO (Equation (41)). All of these components are assembled in the ordered manner with the assistance of an Rh complex. Pyrrolidine as a nucleophile gives the best results. None of the alcohols can participate in a similar transformation. [Pg.498]

This model has been used in the earliest known digital perceptual audio coding system [Krasner, 1979], Similar models have been used for the Low-Complexity-Adaptive Transform Coding (LC-ATC, [Seitzer et al., 1988]) and AC-2 ([Davidson etal., 1990]) systems. [Pg.46]

Contrary to the point by point approach the diagonalization method consists of the generation of an entire lineshape function in one step. (13, 14, 57-60) Time-consuming calculations are carried out only once. The resulting set of complex numbers can be used for a simple calculation of the lineshape (absorption and dispersion modes) at any desired point on the frequency axis. Thus, the complex matrix from equation (147) can be diagonalized by a similarity transformation using an co-independent complex matrix W ... [Pg.262]

Theorem Any matrix can be brought to complex symmetric form by a similarity transformation. [Pg.99]

First we observe that any matrix is similar to a block diagonal matrix, where the sub-matrices along the main diagonal are Jordan blocks. It is thus sufficient to prove that any Jordan block can be transformed to a complex symmetric matrix. In passing we note that any matrix with distinct eigenvalues can be brought to diagonal form by a similarity transformation. The key study therefore relates to XI + J (0), where 1 is the n-dimensional unit matrix and... [Pg.99]

The reoxidation step of the complex takes place after coordination of 02 to the dinuclear Cu complex, forming the complex 6 (Figure 6). The p-dioxo complex is estimated to be formed on the basis of Karlin s model [75]. In the next step the phenolate anion is oxidized by a two-electron transfer to 022- via Cu(II). The resulting complex 7 is similarly transformed into compound 4 (Figure... [Pg.545]

On the Change of Spectra Associated with Unbounded Similarity Transformations of a Many-Particle Hamiltonian and the Occurrence of Resonance States in the Method of Complex Scaling. Part I. General Theory... [Pg.87]


See other pages where Complex similarity transformations is mentioned: [Pg.127]    [Pg.515]    [Pg.469]    [Pg.150]    [Pg.188]    [Pg.20]    [Pg.334]    [Pg.114]    [Pg.24]    [Pg.22]    [Pg.230]    [Pg.166]    [Pg.401]    [Pg.121]    [Pg.30]    [Pg.178]    [Pg.39]    [Pg.347]    [Pg.351]    [Pg.271]    [Pg.266]    [Pg.135]    [Pg.215]    [Pg.403]    [Pg.242]    [Pg.23]    [Pg.44]    [Pg.123]    [Pg.403]    [Pg.242]   
See also in sourсe #XX -- [ Pg.103 , Pg.104 ]




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