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Matrices INDEX

The elements of the matrix, and Q, are themselves matrices. Index a, and b denote the A and B spaces, respectively. The wave functions may be spin orbitals or N-electron wave functions. Equation A.30 consists of two matrix equations. The second of these equations may be written as ... [Pg.491]

This relationship scales the diagonal force constants by the full value of C, where i is the matrix index corresponding to F-, and the off-diagonal coupling constants... [Pg.241]

All of the foregoing equations and diagrams are in the spin-orbital formalisms, meaning that each matrix index carries the attributes of spatial orbital and spin. For instance, the MP2 energy [Eq. (2-29)] is the sum of the contributions from the following four spin combinations ... [Pg.38]

In the equation, a is the proportion of the active substance dissolved and suspended in the gel phase, P is the proportion between the quantities of the active substance found in the droplets and dissolved in the polymer membrane, K is the partition coefficient. Index I shows the partitioning between the liquid and the matrix, index m is the partitioning between the membrane bordering the liquid droplets and the matrix, and index p is the partitioning between the membrane and the acceptor medium. (The same applies to indexes I, m, and p of diffusion constant D.)... [Pg.544]

Fig. 18. Bright-field image of fine particles in a Fe2B matrix and the corresponding EDS spectra for the particles (indexed as A and B) and matrix (indexed as C). Particle B is NdHj, and particle A has shown an EDS spectrum similar to fliat for particle A (Tomida et al. 1996). Fig. 18. Bright-field image of fine particles in a Fe2B matrix and the corresponding EDS spectra for the particles (indexed as A and B) and matrix (indexed as C). Particle B is NdHj, and particle A has shown an EDS spectrum similar to fliat for particle A (Tomida et al. 1996).
The third-order permittivity is described by the third rank tensor Its symmetry properties are similar to those of the piezoelectric tensors. In particular all tensor coordinates vanish for all centro-symmetric crystal classes and the class 432. However, all three indices are interchangeable. As a consequence of this either the first two or the last two indices may be contracted to a single matrix index which allows representation in a 3 by 6 matrix. This offers advantages for tabulation of data but has httle merit otherwise since there is no corresponding matrix index for the respective variables. [Pg.110]

The maximum stress within the fibre is limited by the strain in the fibre (index f ) which can never exceed the matrix (index m ) strain. The maximum possible fibre stress is thus... [Pg.307]

For a given number of a and fi electrons, we can write the coefficient vector as a matrix, indexed by A strings and B strings. [Pg.225]

The matrix indexes run on the basis set orbitals. In Eq. (5.68) P is the density matrix and DH -F G(P) is the vacuum Fock operator F. The other terms represent the interaction of the metal polarization with the charge distribution of the molecule. The interaction of the electrons of the molecule with the nuclei-induced metal polarization is accounted for J, the nuclei-electrons-induced polarization interaction for Y and the electrons-electrons-induced interaction for X(P). They can be recasted in terms on the numerical solution of the electrostatic problems for the electronic... [Pg.245]

Fig. 2.14. Arrangement of phases in the three-shell model of Van der Poel [67] bulk and shear moduli (K, G) and Poisson s ratios vof filler (index 0 and matrix (index a) and volume concentration Vf enter calculated composite moduli K and G (after [76]). Fig. 2.14. Arrangement of phases in the three-shell model of Van der Poel [67] bulk and shear moduli (K, G) and Poisson s ratios vof filler (index 0 and matrix (index a) and volume concentration Vf enter calculated composite moduli K and G (after [76]).
As an example of the static excitation of a chain under these conditions a nearly extended chain of end-to-end distance L embedded in a glassy matrix may be considered. If the matrix (index m) and the chain (no index) were homogeneously strained in chain axis direction they would experience the following stresses ... [Pg.107]

The index J can label quantum states of the same or different chemical species. Equation (A3.13.20) corresponds to a generally stiff initial value problem [42, 43]. In matrix notation one may write ... [Pg.1050]

This is because no four-indexed two-electron integral like expressions enter into the integrals needed to compute the energy. All such integrals involve p(r) or the product p(/)p(r) because p is itself expanded in a basis (say of M functions), even the term p(r)p(r) scales no worse than tvF. The solution of the KS equations for the KS orbitals ([). involves solving a matrix eigenvalue problem this... [Pg.2199]

Multichannel time-resolved spectral data are best analysed in a global fashion using nonlinear least squares algoritlims, e.g., a simplex search, to fit multiple first order processes to all wavelengtli data simultaneously. The goal in tliis case is to find tire time-dependent spectral contributions of all reactant, intennediate and final product species present. In matrix fonn tliis is A(X, t) = BC, where A is tire data matrix, rows indexed by wavelengtli and columns by time, B contains spectra as columns and C contains time-dependent concentrations of all species arranged in rows. [Pg.2967]

The symbol M represents the masses of the nuclei in the molecule, which for simplicity are taken to be equal. The symbol is the Kionecker delta. The tensor notation is used in this section and the summation convention is assumed for all repeated indexes not placed in parentheses. In Eq. (91) the NACT appears (this being a matrix in the electronic Hilbert space, whose components are denoted by labels k, m, and a vector with respect to the b component of the nuclear coordinate R). It is given by an integral over the electron coordinates... [Pg.145]

Figure 2-80. The permutation matrix oFthe reference isomer the second line gives the indices of the sites of the skeleton and the first line the indices of the ligands (e.g.. the ligand with index 3 is on skeleton site 3). Figure 2-80. The permutation matrix oFthe reference isomer the second line gives the indices of the sites of the skeleton and the first line the indices of the ligands (e.g.. the ligand with index 3 is on skeleton site 3).
Figure 6-1. Different forms of representation of a chemical graph a) labeled (numbered) graph b) adjacency matrix c) connectivity table, type I d) connectivity table, type II f) line notations g) structural index. Figure 6-1. Different forms of representation of a chemical graph a) labeled (numbered) graph b) adjacency matrix c) connectivity table, type I d) connectivity table, type II f) line notations g) structural index.
The Wiener index was originally defined only for acyclic graphs and was initially called the path number [6]. "The path number, W, is defined as the sum of the distances between any two carbon atoms in the molecule in terms of carbon-carbon bonds". Hosoya extended the Wiener index and defined it as the half-sum of the off diagonal elements of a distance matrix D in the hydrogen-depleted molecular graph of Eq, (15), where dij is an element of the distance matrix D and gives the shortest path between atoms i and j. [Pg.410]

Because of the symmetry of the distance matrix, the Wiener index can be expressed as Eq. (16). [Pg.410]

With Eq. (16) the Wiener index of compound 2 can be calculated from the distance matrix as shown in Eq, (17)... [Pg.410]

A matrix can be defined as a two-dimensional arrangement of elements (numbers, variables, vectors, etc.) set up in rows and columns. The elements a are indexed as follows ... [Pg.632]

MODIFY - addressing of members of the coefficient matrix are adjusted to allocate their row and column index in the banded matrix. [Pg.212]

The anti symmetrized orbital produet A (l)i(l)2Cl)3 is represented by the short hand (1>1(1>2(1>3 I and is referred to as a Slater determinant. The origin of this notation ean be made elear by noting that (1/VN ) times the determinant of a matrix whose rows are labeled by the index i of the spin-orbital (jii and whose eolumns are labeled by the index j of the eleetron at rj is equal to the above funetion A (l)i(l)2Cl)3 = (1/V3 ) det(( )i (rj)). The general strueture of sueh Slater determinants is illustrated below ... [Pg.241]

When exposed to light, the monomeric material in the photopolymers or photothermoplasts polymerizes, thus locally increasing density and index of refraction. A subsequent fixation process polymerizes the monomer throughout the polymer matrix. [Pg.154]

Passive transdermal dehvery systems on the market tend to be either matrix or membrane controUed. In matrix devices, the stmctural and molecular characteristics of the dmg-polymer matrix determine dmg release. Examples of polymer matrix-controUed diffusional systems for angina prophylaxis include Nitro-Dur and Nitrodisc, which provide transdermal dehvery of nitroglycerin [55-63-0], and Erandol, a tape that releases isosorbide dinitrate [87-33-2]. Matrix diffusional systems have been used for dehvering dmgs with a wide therapeutic index. [Pg.141]

In order to adapt that expression to the problem at hand, we note that interaction matrix elements for shaking and breathing modes are different. Namely, the matrix element AfiV, symmetry index (A or E), is very small for even I + I, while the cosine matrix element, M - = is minor for odd I + I [Wurger 1989]. At low temperatures, when only / = / is accessible, the shaking... [Pg.122]


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See also in sourсe #XX -- [ Pg.651 ]




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