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Elements defining

W (Rj.) is an n X n diabatic first-derivative coupling matrix with elements defined using the diabatic electronic basis set as... [Pg.190]

Requiring l/f (r qx) to be real, the matrix W (Rx) becomes real and skew-symmetiic (just like its adiabatic counterpart) with diagonal elements equal to zero. Similarly, W (Rx) is an n X u diabatic second-derivative coupling matrix with elements defined by... [Pg.190]

Thus far, we have focused exclusively upon the block metals. For some, the term transition elements defines just these J-block species for others, it includes the rare earth or lanthanoid elements, sometimes called the inner transition elements . In this chapter, we compare the elements with respect to their valence shells. In doing so, we shall underscore concepts which we have already detailed as well as identifying both differences and similarities between certain aspects of main and inner transition-metal chemistry. We make no attempt to review lanthanoid chemistry at large. Instead our point of departure is the most characteristic feature of lanthanoid chemistry the +3 oxidation state. [Pg.197]

Since the phenomena studied in fluid dynamics are macroscopic, the fluid is considered to be a continuous medium, and the theory is not based on the behavior of individual molecules in the fluid but, rather, on their averages. Thus, fluid dynamics studies the motion of fluid volume elements which contain a large number of molecules. Such a volume element defines in the continuous medium a point which is small compared to the total system volume, but large when compared to typical intermolecular distances. [Pg.249]

The first step in solving a combinatorial optimization problem is to model the solution space itself. Such a model should be declarative in character, if it is to be independent of the characteristics of the specific algorithm that will be used to find the solution within the solution space. The model we have adopted for the scheduling of flowshop operations is the discrete decision process (DDP) introduced originally by Karp and Held (1967). As defined by Ibaraki (1978) a DDP, Y, is a triple (.S,S,/) with its elements defined as follows ... [Pg.276]

The properties of materials are often critically dependent upon how the elements defined by the bulk analysis are distributed within the structure of the material, and this factor may require that a local analysis be conducted. There are three types of locality we shall consider ... [Pg.228]

Consider the forces acting on the element defined by the points a, b, c, d. Then the normal component (component acting at right angles to the surface) of the pressure force on the element... [Pg.799]

Collectively, the symmetry elements present in a regular tetrahedral molecule consist of three S4 axes, four C3 axes, three C2 axes (coincident with the S4 axes), and six mirror planes. These symmetry elements define a point group known by the special symbol Td. [Pg.144]

The factors which control the distribution of trace elements [defined arbitrarily in geochemistry as those elements present at less than 0.1 weight percent (wt %)] can be discussed under a number of headings - structural, thermodynamic, kinetic and, in the sedimentary environment, solubility and speciation. [Pg.122]

Heat could be generated in the volume element defined by Ar so one has... [Pg.341]

The A(0) and B(0) matrices as defined in Eqs. (41 and 42) depend on the orbital energies and several two-electron integrals collected into the elements defined in Eq. (43). The orbitals are chosen to be real. In this basis the derivatives of orbital energies with respect to a magnetic perturbation are zero. Therefore, only the derivatives of the elements are needed to evaluate A(1) and B(1). [Pg.64]

The supermatrix G, which contains the two-electron repulsion integrals, has elements defined by... [Pg.232]

As for determination of the KS orbitals, we may take a productive approach along the lines of that developed within the context of MO theory in Chapter 4. Namely, we express them within a basis set of functions , and we determine the individual orbital coefficients by solution of a secular equation entirely analogous to that employed for HF theory, except that the elements F y are replaced by elements defined by... [Pg.256]

By standard procedures, using the matrix elements defined by eqs. (11-4), (11-5), and (11-6), the following set of equations is obtained for the coefficients in the representation of zero-order functions (eq. (11-2)) ... [Pg.258]

In exactly the same way, for operators Uk and Vkl we obtain the relationship between the submatrix elements defined relative to the wave functions of partially and almost filled shells... [Pg.171]

There is an overall decrease in TiCL, MgO, FeOtotai, CaO and P2O5 with increasing silica contents, whereas K20 shows the opposite trend. AI2O3 and Na20 have a tendency to increase in the mafic compositions and decrease in the silicic rocks, but with considerable scatter. Ferromagnesian trace elements (i.e. Ni, Cr, Co, Sc, V) and Sr decrease with increasing silica, whereas incompatible elements (e.g. La, Th, Rb, Nb, Ta, Zr) show positive trends (Fig. 8.13). Incompatible elements define smooth positive correlations on inter-element diagrams (Fig. 8.14). [Pg.234]

Trace element abundances of rocks dredged from the Sicily Channel seamounts are scarce (Beccaluva et al. 1981 Calanchi et al. 1989). They show variable concentrations, with incompatible element abundances increasing from tholeiitic to alkaline basalts and basanites (Fig. 8.17). Mantle normalised incompatible elements define bell-shaped patterns (not shown), which resemble those for the exposed rocks in the Sicily Channel. [Pg.241]


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See also in sourсe #XX -- [ Pg.17 , Pg.18 , Pg.21 ]




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Analysis data sets defining elements

Datasets defining elements

Elements Defined by Their Numbers of Protons

Elements, defined

Elements, defined

Finite element method defined

Inner transition elements defined

Main-group elements defined

Periodic table of the elements defined

Transition elements defined

Transposable elements, defined

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