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Unitary structure

Since all the scatterers are identical, their structure factors can be normalised to unitary structure factors, as is always the case for homogeneous structures of normal scatterers [41] ... [Pg.17]

To deal with all the observations h e H in compact form, the unitary structure factor components can be arranged in a vector Urand, and the components of the constraint functions collected in a vector C(x). The MaxEnt distribution of electrons (x) then takes the form... [Pg.17]

Let us start with a set of unitary structure factors which are... [Pg.340]

We start with the process of normalisation in which the raw intensities are converted to unitary structure factors via the equation ... [Pg.346]

We start with the definition of a complex scalar product (also known as a Hermitian inner product, a complex inner product or a unitary structure on a complex vector space. Then we present several examples of complex scalar product spaces. [Pg.81]

Mathematicians should note that we have taken the physicists convention in criterion 1 in many mathematics texts, the dehnition requires Unearity in the first argument. See Exercise 3.4. A complex vector space with a complex scalar product defined on it is known as a complex scalar product space. The complex scalar product is sometimes called a unitary structure on the space. [Pg.82]

Isomorphisms of unitary representations ought to preserve the unitary structure. When they do, they are called unitary isomorphisms of representations. [Pg.133]

Note how important the unitary structure is to Proposition 5.3. If we consider a subrepresentation of a nonunitary representation, then there may not be a complementary representation. Consider, for example, the group G = R (with addition playing the role of the group multiplication), V = and p G defined by... [Pg.156]

Even when there is no unitary structure (i.e., no complex scalar product) on vector spaces V and W, there is a natural complex scalar product on the vector space lloimV, W), given by... [Pg.170]

Not every linear-subspace-preserving function on projective space descends from a complex linear operator. However, when we consider the unitary structure in Section 10.3 we find an imperfect but still useful converse — see Proposition 10.9. [Pg.305]

If the kets label individual states, i.e.. points in projective space, and if addition makes no sense in projective space, what could this addition mean The answer lies with the unitary structure (i.e., the complex scalar product) on V and how it descends to P(y). If V models a quantum mechanical system, then there is a complex scalar product ( , ) on V. Naively speaking, the complex scalar product does not descend to an operation on P(V). For example, if v, w e V 0 and v, w Q v/e have u 2v but (v, w) 2 v, w) = 2v, w). So the bracket is not well defined on equivalence classes. Still, one important consequence of the bracket survives the equivalence orthogonality. [Pg.311]

In this section we have studied the shadow downstairs (in projective space) of the complex scalar product upstairs (in the linear space). We have found that although the scalar product itself does not descend, we can use it to define angles and orthogonality. Up to a phase factor, we can expand kets in orthogonal bases. We will use this projective unitary structure to define projective unitary representations and physical symmetries. [Pg.318]

There are five classes of immunoglobulins that can be distinguished by antigenic determinants on the heavy chains (see later), namely, IgM, IgG, IgA, IgD, and IgE. Antibody activity has been demonstrated in each of the classes. The molecular organization of immunoglobulins is based on a four-chain, unitary structure con-... [Pg.314]

The first important step in this direction was taken by Harker and Kasper (1948), who derived relations between pairs or small groups of reflections in a centrosymmetric structure in the form of inequality expressions. The simplest of these says that if Uhkl is the unitary structure amplitude —the structure amplitude expressed as a fraction of what it would be if the waves from all atoms were exactly in phase with each other f—then... [Pg.429]

The question now arises given some hermitian matrix V and the unitary structure matrices for each cell in the molecule, one can ask is the set of parameters / unique, or are there many distinct sets of AOM parameters (e/) that generate the same matrix V If this latter situation obtains, and in the absence of a physical interpretation of (6-4) it normally does, one may then enquire as to how a computed set of AOM parameters can acquire physico-chemical significance. Although AOM parameters are routinely computed by the best-fit parameter fitting procedure sketched above, the mathematical structure of Eq. (6-4), which to be sure is quite simple, has only recently been discussed ... [Pg.25]

Monolithic catalysts (honeycomb catalysts), in the form of continuous unitary structures that contain small passages. The catalytically active material is present on or inside the walls of these passages. In the former case, a ceramic or metallic support is coated with a layer of material in which active ingredients are dispersed. [Pg.646]

Unitary structure factor The ratio of the structure amplitude F b.kl) to its maximum possible value for point atoms at rest. [Pg.336]

Behavioural genetic analyses provide support for a theory that assumes that the unitary structure of g derives from the influence of genotypes on phenotypic manifestations ofg. Four different kinds of analyses are relevant. [Pg.127]

Monolithic catalysts can be described as continuous unitary structures that contain many small, mostly... [Pg.362]

Structure. Older concepts picturing the basic beryllium compounds as derivatives of condensed acids or as structural analogs of the true basic salts of the other elements have been discarded in favor of unitary structures comparable with those ascribed to other strictly covalent compounds. [Pg.6]

The first mathematical relationships were obtained, starting about 1950, between the sign of phases in centrosymmetric structures in the form of inequalities, later extended to noncentrosymmetric structures, using unitary structure factors. [Pg.5163]

U i in the equation above is the unitary structure factor, defined thus ... [Pg.112]


See other pages where Unitary structure is mentioned: [Pg.113]    [Pg.316]    [Pg.430]    [Pg.431]    [Pg.284]    [Pg.312]    [Pg.809]    [Pg.1]    [Pg.291]    [Pg.291]    [Pg.197]    [Pg.127]    [Pg.124]    [Pg.456]    [Pg.3]    [Pg.38]    [Pg.38]    [Pg.82]    [Pg.470]   
See also in sourсe #XX -- [ Pg.81 , Pg.82 , Pg.113 , Pg.311 ]




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