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Value of coordination

Figure 8. Three-dimensional mean-potential surface for the X IT state of HCCS, (Pi, Pa, y), presented in form of its ID sections. Curves represent the function given by Eq. (75). (with Ati — 0.0414, k2 — 0.952, tt 2 — 0.0184) for fixed values of coordinates p, and P2 (attached at each curve) and variable y — 4 2 4t Here y — 0 corresponds to cis-planar geometry and Y = ft to trans-planar geometry. Symbols results of explicit ab initio computations. Figure 8. Three-dimensional mean-potential surface for the X IT state of HCCS, (Pi, Pa, y), presented in form of its ID sections. Curves represent the function given by Eq. (75). (with Ati — 0.0414, k2 — 0.952, tt 2 — 0.0184) for fixed values of coordinates p, and P2 (attached at each curve) and variable y — 4 2 4t Here y — 0 corresponds to cis-planar geometry and Y = ft to trans-planar geometry. Symbols results of explicit ab initio computations.
In its more advanced aspects, kinetic theory is based upon a description of the gas in terms of the probability of a particle having certain values of coordinates and velocity, at a given time. Particle interactions are developed by the ordinary laws of mechanics, and the results of these are averaged over the probability distribution. The probability distribution function that is used for a given macroscopic physical situation is determined by means of an equation, the Boltzmann transport equation, which describes the space, velocity, and time changes of the distribution function in terms of collisions between particles. This equation is usually solved to give the distribution function in terms of certain macroscopic functions thus, the macroscopic conditions imposed upon the gas are taken into account in the probability function description of the microscopic situation. [Pg.2]

The model of clusters or ensembles of sites and bonds (secondary supramolecular structure), whose size and structure are determined on the scale of a process under consideration. At this level, the local values of coordination numbers of the lattices of pores and particles, that is, number of bonds per one site, morphology of clusters, etc. are important. Examples of the problems at this level are capillary condensation or, in a general case, distribution of the condensed phase, entered into the porous space with limited filling of the pore volume, intermediate stages of sintering, drying, etc. [Pg.300]

Model of a granule of a porous solid as a lattice (labyrinth) of pores and particles, which takes into account the average values of coordination number of bonds and distribution of sites and bonds over the characteristic sizes. [Pg.300]

The methods of structure determination of supported nanoclusters are essentially the same as those mentioned previously for supported metal complexes. EXAFS spectroscopy plays a more dominant role for the metal clusters than for the complexes because it provides good evidence of metal-metal bonds. Combined with density functional theory, EXAFS spectroscopy has provided much of the structural foundation for investigation of supported metal clusters. EXAFS spectroscopy provides accurate determinations of metal-metal distances ( 1-2%), but it gives only average structural information and relatively imprecise values of coordination numbers. EXAFS spectroscopy provides structure data that are most precise when the clusters are extremely small (containing about six or fewer atoms) and nearly uniform (Alexeev and Gates, 2000). [Pg.67]

The Gaussian exponential function, exp(-y2/2cr2), remains finite for all finite values of coordinate y. If interpreted literally, this means that absolute purification is not possible with Gaussian zones because, no matter what their separation, each is contaminated by the residual finite concentration of the other. To get perspective on this problem, assume that the concen-... [Pg.109]

The values of coordinates and velocities (or momenta) at some point in the reactant and product asymptote, respectively, can be used to define the boundary conditions for solving the equations of motion describing an elementary process (18,43). The coordinates Qk = Q, Q2 = Qi and velocities Vl = V, V2 = VJ2j at the end points refer to both the internal and translational degrees of freedom the choice of the end points thus determines the channel as well as the internal (quantized) and translational states of reactants and products. [Pg.257]

The relationships between v (cm-1) and R (M-O) and coordination number (CN) and R (M-O) are shown in Figs 8.38 and 8.39 for Pr(III) and Nd(III) complexes, respectively. The values of v are experimentally measured and the values of R (M-O) are taken from crystal structure data in the literature. Thus knowledge of v will give the value of R (M-O) from Figs 8.38a and 8.39a which in turn give values of coordination number (CN) by using the correlation in Figs 8.38b and 8.39b. [Pg.644]

To start the mathematical integration of the equations of motion for one particular trajectory, a set of initial values of coordinates and either velocities or momenta must be specified. These, however, are dependent on the experimental conditions which need be reproduced, such as collision energy, intramolecular vibrational energies etc... In addition, some other variables, for instance intramolecular instantaneous elongations, molecular orientations, impact parameter, etc..., are necessarily specified in classical mechanics but are not observable microscopically because of the Uncertainty Principle. The ensemble of these result in a set of trajectories associated with a given set of observable initial conditions. [Pg.28]

In the semiclassical regime, the value of coordinate Q must be conserved on transition of an electron from the reactant and the product state under the Franck Condon principle. Since the diabatic potentials for these states are composed of multiple parabolas due to participation of large-energy-quantum intramolecular vibrations, the transition is specified by a simultaneous change in the quantum state of these vibrations, for example, from the wth state m r> in the reactant state to the... [Pg.170]

The pKa values of coordinated water in some metal complexes. [Pg.41]

Whether the inactive region is a true continuum (e.g., photofragmentation) or a quasi-continuum comprised of an enormous density of rigorously bound eigenstates (polyatomic molecule dynamics, Section 9.4.14) is often of no detectable consequence. The dynamical quantities discussed in Section 9.1.4 (probability density, density matrix, autocorrelation function, survival probability, transfer probability, expectation values of coordinates and conjugate momenta) describe the active space dynamics without any reference to the detailed nature of the inactive space. [Pg.683]

A common procedure for solving this overdetermined system is the method of variation of parameters (also referred to in the mathematical literature as Gauss-Newton non-linear least squares algorithm) (Vanicek and Krakiwsky 1982), and this procedure is described in the following. As approximate values of coordinates x° are known a priori, by Taylor s series expansion of the function / about point x°. [Pg.185]

A similar problem to the one considered by Chandra and Fisher (1994) is studied by Fumero and Vercellis (1999). They assume that there is a limited number of vehicles available for product delivery in each time period, whereas no such assumption is made by Chandra and Fisher. They give a different MIP formulation than the one by Chandra and Fisher, and solve it by Lagrangean relaxation. As in Chandra and Fisher (1994), the integrated approach is compared to a decoupled approach in which the production part of the problem is solved first and then the distribution part is solved based on the given solution of production decisions. Similar observations to those obtained by Chandra and Fisher are reported about the value of coordination. [Pg.726]

Value of coordination. A handful of papers (e.g. Chandra and Fisher 1994, Fumero and Vercellis 1999) have studied the value of coordination between production and distribution based on computational experiments on random test problems. It would be very interesting if one could quantify the value of coordination theoretically (e.g. worst-case or average-case analysis) for certain models. This could then be used to decide whether it is worth the effort to consider production and distribution jointly. [Pg.732]

A key feature of the simulation is that coordination—activity to satisfy dependencies—is explicitly analyzed. Coordination activity is real work and must be considered if realistic schedule and cost forecasts are to be generated. Many large complex global projects have 35-45 % of real work associated with collaboration/ communication. Simulation generated forecasts include the demands, feasibility, and value of coordination to overall performance. Risk due to coordination mis-allocation is exposed. [Pg.206]

The lattice parameters a, c and values of coordinates u, v for some crystals are given in fable 2. More details may be found in papers by Aldred (1984), Mdll and Schafer (1971), Lohmuller et al. (1973), Feuss and Kallel (1972), and Radhakrishna et al. (1981). The Bravais lattice in this case is also a body-centered tetragonal, the first two coordination spheres of a rare-earfli ion consist of two fours of oxygen ions. Rare-earth ions are distributed with almost the same density as in tetrafluorides. [Pg.304]


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See also in sourсe #XX -- [ Pg.726 , Pg.732 ]




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Coordination value

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