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Hyper-complex

The hyper-Kahler structure is a quaternionic version of the Kahler structure. However, there is no good definition of the integrability (i.e. the existence of local charts) for the almost hyper-complex structure. Hence we generalize the second equivalent dehnition explained in above. [Pg.33]

Metalloporphyrins containing low valent main group elements show hyper-type UV-visible spectra and the corresponding higher valent complexes show normal spectra. Despite this, the phosphorus complexes [P(OEP)R2] show spectra with distinctly hyper character, with two extra Soret bands apparent. The extra Soret band in hyper complexes has been assigned to charge transfer from the low... [Pg.326]

Since the G-action on // 1(C) is free, the slice theorem implies that the quotient space gTl((,)/G has a structure of a C°°-manifold such that the tangent space TaAtt-HO/G) at the orbit G x is isomorphic to the orthogonal complement of Vx in Txg 1( ). Hence the tangent space is the orthogonal complement of Vx IVX JVX KVX in TxX, which is invariant under I, J and K. Thus we have the induced almost hyper-complex structure. The restriction of the Riemannian metric g induces a Riemannian metric on the quotient g 1(()/G. In order to show that these define a hyper-Kahler structure, it is enough to check that the associated Kahler forms u>[, u) 2 and co z are closed by Lemma 3.32. [Pg.36]

If the phase cycling used selects only one coherence transfer pathway, a two-dimensional spectrum with phase-twist lineshapes is obtained. However, the experiment can be easily modified to ensure that pure absorption (pure phase) lineshapes are obtained. The most commonly used modified acquisition schemes that allow pure-phase MQMAS spectra to be obtained include amplitude-modulated experiments, with hyper-complex (States) acquisition, and phase-modulated experiments, with delayed acquisition such as shifted echo or antiecho and split-methods. [Pg.154]

Fig. 7 Comparison of alternative processing on a 3D N-NOESY-HSQC spectrum of human translation initiation factor eIF4e. (a) Uniformly sampled reference. The time domain data were acquired as 6,400 hyper-complex points sampled in the two indirect dimensions [128 (Hjndir) x 50 ( N)]. The spectra were measured on a 700-MHz spectrometer with sweep widths of 9765 Hz and 2270 Hz, respectively. The t ,ax hence were 0.013 and 0.022 s each for the indirect proton and nitrogen dimensions, respectively, representing nearly an optimal situation for the nitrogen dimension, but not for the indirect proton dimension. Data were transformed with the standard KFT procedure after cosine apodization and doubling the time domain by zero filling, (b) Reducing the number of complex points to 42 (32%) (bl) and 13 (10%) (b2) in the indirect proton dimension, cosine apodization, and zero filling result in low resolution spectra in the indirect... Fig. 7 Comparison of alternative processing on a 3D N-NOESY-HSQC spectrum of human translation initiation factor eIF4e. (a) Uniformly sampled reference. The time domain data were acquired as 6,400 hyper-complex points sampled in the two indirect dimensions [128 (Hjndir) x 50 ( N)]. The spectra were measured on a 700-MHz spectrometer with sweep widths of 9765 Hz and 2270 Hz, respectively. The t ,ax hence were 0.013 and 0.022 s each for the indirect proton and nitrogen dimensions, respectively, representing nearly an optimal situation for the nitrogen dimension, but not for the indirect proton dimension. Data were transformed with the standard KFT procedure after cosine apodization and doubling the time domain by zero filling, (b) Reducing the number of complex points to 42 (32%) (bl) and 13 (10%) (b2) in the indirect proton dimension, cosine apodization, and zero filling result in low resolution spectra in the indirect...
B(A) is the probability of observing the system in state A, and B(B) is the probability of observing state B. In this model, the space is divided exactly into A and B. The dividing hyper-surface between the two is employed in Transition State Theory for rate calculations [19]. The identification of the dividing surface, which is usually assumed to depend on coordinates only, is a non-trivial task. Moreover, in principle, the dividing surface is a function of the whole phase space - coordinates and velocities, and therefore the exact calculation of it can be even more complex. Nevertheless, it is a crucial ingredient of the IVansition State Theory and variants of it. [Pg.276]

Hyper-Branched Polymers Based on Aryl-Metal Complexes. 44... [Pg.39]

Hyper-Branched Polymers Based on Alkynyl-Metal Complexes. 48... [Pg.39]

Reinhoudt and coworkers studied the synthesis of hyper-branched polymers composed of organopalladium complexes with an SCS pincer ligand [11]. Removal of acetonitrile ligands on palladium led to the self-assembly of dinu-clear palladium complex (9) to give hyper-branched polymer (10), which was... [Pg.44]

In Chapter 29 we introduced the concept of the two dual data spaces. Each of the n rows of the data table X can be represented as a point in the p-dimensional column-space S . In Fig. 31.2a we have represented the n rows of X by means of the row-pattern F. The curved contour represents an equiprobability envelope, e.g. a curve that encloses 99% of the points. In the case of multinormally distributed data this envelope takes the form of an ellipsoid. For convenience we have only represented two of the p dimensions of SP which is in reality a multidimensional space rather than a two-dimensional one. One must also imagine the equiprobability envelope as an ellipsoidal (hyper)surface rather than the elliptical curve in the figure. The assumption that the data are distributed in a multinormal way is seldom fulfilled in practice, and the patterns of points often possess more complex structure than is shown in our illustrations. In Fig. 31.2a the centroid or center of mass of the pattern of points appears at the origin of the space, but in the general case this needs not to be so. [Pg.104]

More recent experiments using even higher shock wave pressures, up to around 40 GPa (produced by a hyper-velocity impact gun) show that the extremely short periods of time (only a few microseconds) for which the pressure is applied have a lower decomposing effect on the amino acids in aqueous solution, and in ice, than had been expected. The exact analysis of the products showed that small amounts of simple peptides were also formed. These results point to the complexity of questions on biogenesis problems. Even cannon can help us in our attempts to reveal the secret of biogenesis ... [Pg.114]

T. Baker, DuPont Central Research In reference to your so-called iso-closo iridaborane complex, H(PPh3)2IrB9H9, we have recently published two papers (1,2) dealing with isoelec-tronic, isostructural ten-vertex ruthenacarborane complexes and have demonstrated that these structures are related to the common closo bicapped square antiprismatic structure by the removal of two electrons (i.e. 2N skeletal electrons for an N vertex polyhedron). Such complexes have been referred to as hyper-closo to imply that the electronic unsaturation is not primarily metal-based (as in, for example, nido-(PPh3)2RhC2B8-Hx 2 (3) or closo-(PPh3)ClRh(1,7-C,BQH,) (4), but is delocal-... [Pg.334]

Monomeric carbene complexes with 1 1 stoichiometry have now been isolated from the reaction of 4 (R = Bu, adamantyl or 2,4,6-trimethylphenyl R = H) with lithium l,2,4-tris(trimethylsilyl)cyclo-pentadienide (72). The crystal structure of one such complex (R = Bu) revealed that there is a single cr-interaction between the lithium and the carbene center (Li-C(carbene) 1.90 A) with the cyclopentadienyl ring coordinated in an if-fashion to the lithium center. A novel hyper-valent antimonide complex has also been reported (73). Thus, the nucleophilic addition of 4 (R = Mes R = Cl) to Sb(CF3)3 resulted in the isolation of the 1 1 complex with a pseudo-trigonal bipyramidal geometry at the antimony center. [Pg.29]

The ethynyl-linked complexes 105 were prepared and explored as potential building blocks for nonlinear optical (NLO) materials.129 Spectroscopic and cyclic voltammetry data indicate a small but real interaction between the ferrocenyl donor group and the borabenzene unit, increasing in the order RuHyper-Rayleigh scattering revealed small values for the first hyperpolarizability / , which increases in the same order. [Pg.36]

The architecture dependence is also demonstrated in Fig. 33 by the factors of several star macromolecules, flexible cychc chains. Randomly and hyper-branched materials show a more complex behavior because of the large width in the molar mass distribution. Table 5 gives the actual values. The plot of Fig. 33 shows nicely how for a large number of arms the factor for hard spheres is approached. [Pg.181]

For more complex mechanisms, picturesque names such as square, ladder, fence [18] or cubic schemes [20] have been selected. In redox polymer films, additional transport of counterions, solvation, and polymer reconfiguration are important and four-dimensional hyper-cubes are needed to describe the reactions [21]. [Pg.6]

At a slightly deeper level, the difficulty of this approach lies in its acceptance of a transition complex in which the original classification into a and tt electrons has been broken consequently pure tt electron theory is inadequate for the prediction of energy changes, and a complete analysis must await the inclusion of the a bond modifications at the point of attack. Preliminary attempts to include such effects have invoked hyper conjugation (Muller et al., 1954 Fukui et al., 1954a) and other factors (Dewar et al., 1956), but little progress has yet been made towards a more detailed theoretical interpretation based on more complete calculations. [Pg.103]

The question of the effect of the —CH2-group which is present after proton addition is connected with the question as to the extent to which hyperconjugation in methyl-substituted proton addition complexes has to be taken into account. This question was treated in detail in an investigation of the proton addition complex of benzene by Muller et al. (1954). In an MO calculation, the effect of this CH2-group was treated as a hyper conjugation effect. In contrast to a simple HMO calculation without overlap, the overlap between adjacent C-atoms was taken into account. The calculations were based on the model ... [Pg.290]


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See also in sourсe #XX -- [ Pg.154 ]




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