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Isometry defined

Confining and asymptotic GED states A hint at molecular structure. The change from a configuration space where the nuclear wave function is defined to a special role as the positive source (nuclear) configuration space Q in eq. (7), is achieved by an isometry mapping the distances are invariant but the ideology is changed. [Pg.186]

We observe that / is also called the statistically homogeneous (i.e. stationary) random process. Statistical homogeneity means that two geometric points of the space are statistically undistinguishable, or the statistical properties of the medium are invariant under the action of translation. Then we have a group C/x x lRn of isometries on L2(fi) = L2(Q,F, pt) defined by... [Pg.118]

An immediate consequence of Pasteur s law is that the relationship between enantiomers is established by symmetry alone and does not require any knowledge of molecular bonding connectedness (constitution). This is in contrast to diastereomers, the other class of stereoisomers Diastereomers are not related by symmetry, and their relationship can be defined only by first specifying that their constitutions are the same—otherwise, there would be nothing to distinguish them from constitutional isomers. Thus enantiomers, which have identical scalar properties and differ only in pseudoscalar properties, have more in common with homomers than with diastereomers, while diastereomers, which differ in all scalar properties, have more in common with constitutional isomers than with enantiomers.51, 52 It therefore makes more sense, in an isomer classification scheme, to give priority to isometry rather than to constitution.52 In such a scheme there is no need for the concept stereoisomer the concept retains its usefulness only because it normally proves convenient, in chemical reaction schemes, to combine enantiomers and stereoisomers in a common class. [Pg.27]

Example 10. Translation. Translation cannot be represented as a matrix transformation (C.l). It is, however, an isometric operation, i.e. preserves the distances among the points of the transformed object. This is sufficient for us. Let us enlarge the set of the allowed operations in 3D Euclidean space by isometry. Similarly, as in the case of rotations let us define a shift of the function f(r). A shift of function f(r) by vector ri is such a transformation TZ(ri) (in the Hilbert space) that the new function f (r) = f(r-ri). As an example let us take function f(r) = exp[— r—pqPi and let us shift it by vector rj. Translations obey the known relation (C.2) ... [Pg.909]

Figure 2 shows the sensitivity of Debye correlation function to the change of parameter a which is defined in Eq. (10). As we explained in Section on Theory of scattering, a = 0 corresponds to an isometric two-component system and x 0 a non-isometric system. When x = 0.1 a two-component system becomes a non-isometric system with volume fractions, cpi = 0.46 and q>2 = 0.54. The Debye correlation functions for two cases, a = 0 and X = 0.1, were calculated with a set of representative values of a, b and c. Figure 2 shows that a small deviation from isometry does not affect shape of the Debye correlation function. All our samples were prepared so that they are isometric at a reference salinity, and the change of an effective volume fraction as a function of salinity is expected less than 10%. Therefore, we treat the parameter a as effectively zero in all data analysis. [Pg.30]


See other pages where Isometry defined is mentioned: [Pg.362]    [Pg.186]    [Pg.83]    [Pg.60]    [Pg.20]    [Pg.107]    [Pg.180]    [Pg.1080]    [Pg.453]    [Pg.91]    [Pg.95]   
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