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Absolute minima

The above expressions for the energies are calculated by supposing that the D3 extrema are absolute minima. When the D3 extrema lie on the lowest sheet of the APES, the condition... [Pg.98]

If none of the three relocations of the mobile point with respect to the centroid act to lower its squared error, then the program uses scaling to move all of the points away from the one with the least squared error. Scaling is useful to shake loose the simplex from a local minima, and allow it to propagate toward the absolute minima of squared error. Repeated scaling without any change in the point of lowest squared error indicates either that the solution has been found, or that the program could not break out of a local minima. [Pg.146]

For the models derived herein, the program was able to converge on the absolute minima—the correct coefficients. For... [Pg.151]

The cross-sectional area of the solid phase perpendicular to the skeleton edge is calculated along all skeleton branches of the solid phase. The solid phase is then disconnected at the points corresponding to the absolute minima of that cross-sectional area for every skeleton edge (branch) cf. Grof et al. (2003). Examples of solid-phase fragments of the porous media formed by the disconnection of the solid-phase skeleton at weak points are shown in Figures 11 and 12. [Pg.161]

Figure 11. Structures of clusters of atoms calculated with pairwise additive Lennard-Jones potentials for n = 7 to 19 atoms. The structures are believed to be the absolute minima in the potential energy surface and correspond to 0 K classical calculations. The shaded atom corresponds to the particle being added to the preceding cluster. Clusters in the same column gain the same number of nearest neighbors with the addition of the shaded atom. Figure 11. Structures of clusters of atoms calculated with pairwise additive Lennard-Jones potentials for n = 7 to 19 atoms. The structures are believed to be the absolute minima in the potential energy surface and correspond to 0 K classical calculations. The shaded atom corresponds to the particle being added to the preceding cluster. Clusters in the same column gain the same number of nearest neighbors with the addition of the shaded atom.
From the data reported in this work, we obtain Table 5.5, which gives the relative stability A of H-bonded with respect to anti-H-bonded structures in the whole series of heterodimers.The distances for the heavier rare gases (Ar, Kr, Xe) are those given by Hutson and Howard (1982) for the well depths of the potentials at the absolute minima of the H-bonded structures. The experimental values of the dipole polarizabilities a of the Rg gases taken from Soldan etal. (2001) are given in the second column of the table. It is seen that the stability of the H-bonded structures increases with the dipole polarizability of the heavier rare gases. [Pg.199]

The Al4" unit with different total charge n (n = —2, —1,0, and 1) has been fully optimized for each case to assess electronic charge and spin effects on the geometry. The detailed geometrical parameters are summarized in Table 2. A frequency analysis is done to confirm that all obtained geometries are at absolute minima. It can be noted that only when the total charge is —2, a stable planar structure is obtained. For other charges, rhomboids are favored. [Pg.209]

The first insights that can be gathered from Figs. 7.30 and 7.31 are that the maximum productivity of SMB is about five times greater. Although the absolute minima of eluent consumption are not visible in Fig. 7.31, it is still obvious that the achievable value for eluent consumption in SMB processes is lower than in batch processes. Further advantages of SMB over batch chromatography appear if we take a... [Pg.367]

The BALTIC climatology provided digitally in the supplement (see Chapter 20) reports the absolute minima and maxima for each particular parameter in each month of the year in each cell of the BALTIC volume. These extremes may be used as confidence intervals for assessing the validity of archived data or future observations. [Pg.320]

Calculations on the [C7H7] ion, for the most part by MINDO/3, indicate that the ring should be planar, and that electronic structures (LIV) and (LV) represent absolute minima on the potentia surface [380]. [Pg.297]

Chemistry is the behavior of electrons pushing point-like nuclei with charge +Ze to mutual distances representing (relative or absolute) minima of energy... [Pg.197]

The relative and absolute minima of (4.3) can easily be calculated. It is found... [Pg.152]

Absolute minima are determined by a "Maxwell line" construction. [Pg.153]

Fig. 7. Cubic T x (e x 12) problem domains of existence of absolute minima of a given symmetry type, as a function of the vibronic coupling constants E4 and 5. In the border region between two domains, minima of the adjacent symmetry types may coexist. A special solution is found for parameter values on the borderline between D4, and D21, minima along this line the minima form a continuous mesh, connecting all tetragonal and orthorhombic points... Fig. 7. Cubic T x (e x 12) problem domains of existence of absolute minima of a given symmetry type, as a function of the vibronic coupling constants E4 and 5. In the border region between two domains, minima of the adjacent symmetry types may coexist. A special solution is found for parameter values on the borderline between D4, and D21, minima along this line the minima form a continuous mesh, connecting all tetragonal and orthorhombic points...
Thus, for termination by combination, the polydispersity of the dead chains will have a minimum polydispersity of 1.5. For systems with both disproportionation and combination, the minimum polydispersity will be somewhere between 1.5 and 2.0, depending on the relative rates of the two termination mechanisms. In both cases, the minimum values of polydispersity are absolute minima, and not likely to be attained in practice. The derivations of the minima assume constant temperature, constant monomer concentration (clearly not possible in a batch reactor), constant radical flux, and perfect mixing. For these reasons, actual polydispersities will always be greater than the appropriate minimum. [Pg.337]


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See also in sourсe #XX -- [ Pg.59 , Pg.60 , Pg.61 , Pg.139 , Pg.167 ]




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