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Scalar addition coefficients

Recurrence relations for the scalar and vector addition theorem has also been given by Chew [32,33], Chew and Wang [35] and Kim [U ]- The relationship between the coefficients of the vector addition theorem and those of the scalar addition theorem has been discussed by Bruning and Lo [29], and Chew [32]. [Pg.287]

Exercise 2.1 Consider the set of homogeneous polynomials in two variables with real coefficients. There is a natural addition of polynomials and a natural scalar multiplication of a polynomial by a complex number. Show that the set of homogeneous polynomials with these two operations is not a complex vector space. [Pg.70]

Multiplication of the Dirac characters produces a linear combination of Dirac characters (see eq. (4.2.8)), as do the operations of addition and scalar multiplication. The Dirac characters therefore satisfy the requirements of a linear associative algebra in which the elements are linear combinations of Dirac characters. Since the classes are disjoint sets, the Nc Dirac characters in a group G are linearly independent, but any set of N< I 1 vectors made up of sums of group elements is necessarily linearly dependent. We need, therefore, only a satisfactory definition of the inner product for the class algebra to form a vector space. The inner product of two Dirac characters i lj is defined as the coefficient of the identity C in the expansion of the product il[ ilj in eq. (A2.2.8),... [Pg.439]

The latter free energy can be represented as a surface integral over the solvent accessible surface of the molecule on the basis of a local free energy surface density (FESD) p. This surface density function is represented in terms of a three-dimensional scalar field which is comprised of a sum of atomic increment functions to describe lipophilicity in the molecular environment.The empirical model parameters are obtained by a least squares procedure with experimental log P values as reference data. It is found that the procedure works not only for the prediction of unknown partition coefficients but also for the localization and quantification of the contribution of arbitrary fragments to this quantity. In addition, the... [Pg.230]

These are expressed in terms of scalar products between the unit axis system vectors on sites 1 and 2 (on different molecules) and the unit vector 6. from site 1 to 2. The S functions that can have nonzero coefficients in the intermolecular potential depend on the symmetry of the site. This table includes the first few terms that would appear in the expansion of the atom-atom potential for linear molecules. The second set illustrate the types of additional functions that can occur for sites with other than symmetry. These additional terms happen to be those required to describe the anisotropy of the repulsion between the N atom in pyridine (with Zj in the direction of the conventional lone pair on the nitrogen and yj perpendicular to the ring) and the H atom in methanol (with Z2 along the O—H bond and X2 in the COH plane, with C in the direction of positive X2). The important S functions reflect the different symmetries of the two molecules.Note that coefficients of S functions with values of k of opposite sign are always related so that purely real combinations of S functions appear in the intermolecular potential. [Pg.232]

If spin-orbit effects are considered in ECP calculations, additional complications for the choice of the valence basis sets arise, especially when the radial shape of the / -f-1/2- and / — 1/2-spinors differs significantly. A noticeable influence of spin-orbit interaction on the radial shape may even be present in medium-heavy elements as 53I, as it is seen from Fig. 21. In many computational schemes the orbitals used in correlated calculations are generated in scalar-relativistic calculations, spin-orbit terms being included at the Cl step [244] or even after the Cl step [245,246]. It therefore appears reasonable to determine also the basis set contraction coefficients in scalar-relativistic calculations. Table 9 probes the performance of such basis sets for the fine structure splitting of the 531 P ground state in Kramers-restricted Hartree-Fock [247] and subsequent MRCI calculations [248-250], which allow the largest flexibility of... [Pg.842]

In addition to the electronically adiabatic representation described by (4) and (5) or, equivalently (57) and (58), other representations can be defined in which the adiabatic electronic wave function basis set used in expansions (4) or (58) is replaced by some other set of functions of the electronic coordinates rel or r. Let us in what follows assume that we have separated the motion of the center of mass G of the system and adopted the Jacobi mass-scaled vectors R and r defined after (52), and in terms of which the adiabatic electronic wave functions are i] l,ad(r q) and the corresponding nuclear wave function coefficients are Xnd (R). The symbol q(R) refers to the set of scalar nuclear position coordinates defined after (56). Let iKil d(r q) label that alternate electronic basis set, which is allowed to be parametrically dependent on q, and for which we will use the designation diabatic. We now proceed to define such a set. LetXn(R) be the nuclear wave function coefficients associated with those diabatic electronic wave functions. As a result, we may rewrite (58) as... [Pg.430]

Only six coefficients are required to characterize the coupling dyadic at the center of reaction. But then an additional three scalars are required to specify the location of this point, so that the total number of independent scalars required for a complete characterization is still nine. Similarly, three scalars suffice for the translation dyadic if we refer them to the principal axes of translation [see Eq. (44)], but then three additional scalars (e.g., an appropriate set of Eulerian angles) are required to specify the orientations of these axes. So it comes down to the same thing—namely, that six scalars are required. The same is true of the rotation dyadic at any point, and of the coupling dyadic at the center of reaction. [Pg.302]

We can immediately identify two parity conserving terms, which arise from the scalar products of the two vectorial currents with the coupling coefficients Qy, Qy on the one hand and of the two axial currents with coupling coefficients 9, 9 on the other hand. In addition, we obtain two parity violating contributions from the two axial current-vectorial current couplings, which are often abbreviated as Vf Af and A/,V/j. Each of these terms has a time-like and a space-like component. [Pg.222]

The operator, exp (k/), is symmetric in the entropic scalar product. This enables the formulation of symmetry relations between observables and initial data, which can be validated without differentiation of empirical curves and are, in that sense, more robust and closer to direct measurements than the classical Onsager relations. In chemical kinetics, there is an elegant form of symmetry between A produced from B and B produced from A their ratio is equal to the equilibrium coefficient of the reaction A B and does not change in time. The symmetry relations between observables and initial data have a rich variety of realizations, which makes direct experimental verification possible. This symmetry also provides the possibility of extracting additional experimental information about the detailed reaction mechanism through dual experiments. The symmetry relations are applicable to all systems with microreversibility. [Pg.194]

Matrices are rectangular arrays of numbers and obey the rules (7.105)-(7.107) for addition, scalar multiplication, and matrix multiplication. If / is a complete, orthonormal set of functions, then the matrix A with elements A = fm A fn) represents the linear operator A in the / basis. Also, the column matrix u with elements m, equal to the coefficients in the expansion u = represents the function u in the / basis. The matrix representatives of operators and functions in a given basis obey the same relations as the operators and functions. For example, if C = A + B,R = Sf, and w = Au, then C = A -I- B, R = ST, and w = Au. [Pg.191]

The parameter F is used to represent the diffusion coefficient for the scalar 4). If 4) is one of the components of velocity, for example, F would represent the viscosity. All sources are collected in the term S. Again, if 4> is one of the components of velocity. S would be the sum of the pressure gradient, the gravitational force, and any other additional forces that are present. The control volume has a node, P, at its center where all problem variables are stored. The transport equation describes the flow of the scalar 4> into and out of the cell through the cell faces. To keep track of the inflow and outflow, the four faces are labeled with lowercase letters representing the east, west, north, and south borders. The neighboring cells also have nodes at their centers, and these are... [Pg.277]

The first two terms are the usual classical OR addition of probabilities we can get to state a either through route lor through route 3. The second set of terms in Eq. (7.14) is tile, by now, famihar interference between the two classical alternatives. There are two control parameters because the magnitude of the interference is governed by the absolute values of the two experimental coefficients and, separately, by tiieir relative phase. We could write that CjCs = ciC31 exp(i( 73 - 7i)) and so conclude that it is the phase difference 3 - between the two paths that determines tiie interference. This is almost, but not quite, correct. The properties of the molecule also enter in wave functions in the continuum are complex numbers and so have a phase. Scalar products such as (V a I V i) are therefore complex numbers. If we want to emphasize interference we should rewrite Eq. (7.14) as... [Pg.321]

In addition, it is assumed that the matrix L formed by the phenomenological coefficients is positive definite, i.e., Ylj f. jLjk k > 0 for any set of arbitrary scalar quantities < > . ... [Pg.265]


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