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Complex resonance theory

Neuronal networks are nowadays predominantly applied in classification tasks. Here, three kind of networks are tested First the backpropagation network is used, due to the fact that it is the most robust and common network. The other two networks which are considered within this study have special adapted architectures for classification tasks. The Learning Vector Quantization (LVQ) Network consists of a neuronal structure that represents the LVQ learning strategy. The Fuzzy Adaptive Resonance Theory (Fuzzy-ART) network is a sophisticated network with a very complex structure but a high performance on classification tasks. Overviews on this extensive subject are given in [2] and [6]. [Pg.463]

The localization method was originally described by Wheland (1942) with reference to resonance theory, the activated complex being considered as a resonance hybrid consisting of a variable mixture of structures including (I) and (II). [Pg.102]

Several approaches exist to understanding the structure of metal carbenes. Perhaps the simplest and most familiar is resonance theory. Structures 10-13 represent several possible contributing resonance structures of metal carbenes. Structures 10-12 seem to be important contributors for Fischer carbene complexes, as indicated by experiment and calculations. [Pg.400]

It should be pointed out, however, that resonance theory is misleading regarding the true nature of the M-C bond in a Fischer-type carbene complex. It turns out that the barrier to rotation about the M-C bond is low because a n bond exists, regardless of the degree of rotation. Molecular orbital theory (described later in Chapter 10) does a much better job of explaining the apparent dichotomy between the presence of a formal M=C bond and a low-rotational-energy barrier. [Pg.400]

The interaction of deuterated and chlorinated acetonitrile, CD3CN and CCI3CN, respectively, with Bronsted acid sites of H-ZSM-5 and H,D-ZSM-5 and the thus-induced changes in the IR spectra were interpreted by Pehnenschikov et al. [657] in the frame of the resonance theory of the A-B-C triplet, developed for molecular H-complexes. The approach was similar to that of water adsorption (vide supra). Kotrla and Kubelkova [729] discussed in great detail the spectral features observed on the adsorption of deuterated acetonitrile, designated as... [Pg.139]

Since the present differential equation, Eq. (3), derives from a complex symmetric structure, there are two main consequences, namely, (i) under appropriate perturbations there appears generic complex resonance energies and (ii) it may not be possible to bring the matrix to a diagonal form. As an example of a mathematically rigorous development, we mention the theory of dilation analytic operators [11] of current use in atomic and molecular physics. Hence, the theory outlined here should apply to atomic and molecular systems and their antiparticle partners. Considering initially the first point (the second point will be handled in the following sections), we make the apposite replacements... [Pg.76]

Linus Carl Pauling (1901-1994), American physicist and chemist, in the years 1931-1964 professor at the Calitbmia Institute of Technology in Pasadena, in 1967-1969 professor at the University of California, San Diego, from 1969-1974 professor at the Starrfbrd University. Me received the 1954 Nobel prize for his research into the nature of the chemical bond and its application to the efucidsrSon of the structure of complex substanced". In 1962 he received the Nobel peace prize. His major achievements are the development of fhe fhe-ory of chemical bond, i.a., the VB method (also called resonance theory), and determining fhe... [Pg.523]


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See also in sourсe #XX -- [ Pg.114 ]




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