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Optimal derivative order

Note that Eqs. (10.29) and (10.30) take the vibrational frequencies as independent variables, and as such cannot be calculated ab initio without first optimizing a structure at some level of theory and then computing the second derivatives in order to obtain the frequencies within the harmonic oscillator approximation. (Of course, one could avoid the harmonic oscillator approximation (see, for example, Barone 2004), but tlie necessary calculations and... [Pg.365]

This work deals with the selection of strains of N2-fixing blue-green algae on the basis of biomass composition, productivity and tolerance to temperature and pH. Outdoor culture of the most adequate strains has been tested in order to derive optimal conditions for growth. [Pg.179]

Irradiation of the 2-bromo-derivatives of norbornane in methanol gave a higher ratio of radical to ionic products with an overall lower material balance than the corresponding photoreaction of the 2-iodo derivatives. In order to optimize ionic photobehavior in both the bromo- and iodo-photoreactions, hydroxide ion was added to scavenge HX, which is both a strong acid and a... [Pg.73]

Below we show a derivative version, called ELS for equidistant least squares, that uses the same algorithm but with easier-to-make input boxes. It provides two options a fixed or a variable (self-optimizing) order, selected by the macros ELSfixed and ELSoptimized respectively. The main program is the subroutine ELS, which itself calls on several functions and on a subroutine, ConvolutionFactors. The latter need not be a separate subroutine, since it is only called once in the program. However, by placing it in a separate subroutine it becomes available for use in other programs, such as Interpolation, that could benefit from it. [Pg.451]

Now we proceed to design Pareto-optimal QF contracts for the supply chain under the satisficing objectives. For the clarity of exposition, we first summarize our results on Pareto-optimal QF contracts in Table 4 (see the Appendix for a derivation). The second column ofthe table identifies the conditions for the contract parameter set 0 to be Pareto optimal. The associated Pareto-optimal order quantity and maximal probabilities of achieving their target profits are given by P 0) and P (0), respectively. [Pg.242]

One of the first to consider pricing and inventory decisions for products experiencing deterioration in demand is Cohen [39]. The author considers a modified Economic Order Quantity (EOQ) model with production set-up costs and zero inventory at the beginning of each cycle, where the objective is to determine a price and order quantity for each cycle. Cohen assumes demand is a deterministic linear function of price with exponential decay that is proportional to the on-hand inventory, and he derives the profit maximizing solution. Sensitivity analysis indicates that for a fixed price, the optimal cycle length decreases as the decay rate increases. Further, the optimal order rate increases with an increase in the decay rate and decreases with increasing price if price is an external parameter. [Pg.350]

The optimal order frequency minimizes the total annual cost and is obtained by taking the first derivative of the total cost with respect to n and setting it equal to 0. This results in the optimal order frequency n, where... [Pg.281]

A more rigorous derivation of the previously mentioned formula is provided in Appendix 13A. The optimal CSL has also been referred to as the critical fractile. The resulting optimal order quantity maximizes the firm s profit. If demand during the season is normally distributed, with a mean of jx and a standard deviation of a-, the optimal order quantity is given by... [Pg.366]

Optimal order quantity in period 1 To derive the S3mimetric Nash equilibrium first period stock levels Q, we take other retailers decisions Q - Q > Q > > 2 ) 3s given and derive retailer i s optimal decision Q.. [Pg.151]

This paper is structured as follows in section 2, we recall the statement of the forward problem. We remind the numerical model which relates the contrast function with the observed data. Then, we compare the measurements performed with the experimental probe with predictive data which come from the model. This comparison is used, firstly, to validate the forward problem. In section 4, the solution of the associated inverse problem is described through a Bayesian approach. We derive, in particular, an appropriate criteria which must be optimized in order to reconstruct simulated flaws. Some results of flaw reconstructions from simulated data are presented. These results confirm the capability of the inversion method. The section 5 ends with giving some tasks we have already thought of. [Pg.327]

Th c Newton-Raph son block dingotial method is a second order optim izer. It calculates both the first and second derivatives of potential energy with respect to Cartesian coordinates. I hese derivatives provide information ahont both the slope and curvature of lh e poten tial en ergy surface, Un like a full Newton -Raph son method, the block diagonal algorilh m calculates the second derivative matrix for one atom at a lime, avoiding the second derivatives with respect to two atoms. [Pg.60]

To fin d a first order saddle poiri t (i.e., a trail sition structure), a m ax-imiim must be found in on e (and on/y on e) direction and minima in all other directions, with the Hessian (the matrix of second energy derivatives with respect to the geometrical parameters) bein g varied. So, a tran sition structu re is ch aracterized by th e poin t wh ere all th e first derivatives of en ergy with respect to variation of geometrical parameters are zero (as for geometry optimization) and the second derivative matrix, the Hessian, has one and only one negative eigenvalue. [Pg.65]

Perform an optimization of these two derivatives at the PM3 or RHF/STO-3G level in order to discern which is the more favorable isomer (the latter is a very long job). What are the most dramatic structural features that characterize these two isomers Do the bridging carbons remain bonded in the derivative ... [Pg.54]

In such cases the expression from fii st-order perturbation theory (10.18) yields a result identical to the first derivative of the energy with respect to A. For wave functions which are not completely optimized with respect to all parameters (Cl, MP or CC), the Hellmann-Feynman theorem does not hold, and a first-order property calculated as an expectation value will not be identical to that obtained as an energy derivative. Since the Hellmann-Feynman theorem holds for an exact wave function, the difference between the two values becomes smaller as the quality of an approximate wave function increases however, for practical applications the difference is not negligible. It has been argued that the derivative technique resembles the physical experiment more, and consequently formula (10.21) should be preferred over (10.18). [Pg.241]

Many problems in computational chemistry can be formulated as an optimization of a multidimensional function/ Optimization is a general term for finding stationary points of a function, i.e. points where tlie first derivative is zero. In the majority of cases the desired stationary point is a minimum, i.e. all the second derivatives should be positive. In some cases the desired point is a first-order saddle point, i.e. the second derivative is negative in one, and positive in all other, directions. Some examples ... [Pg.316]

A few comments on the layout of the book. Definitions or common phrases are marked in italic, these can be found in the index. Underline is used for emphasizing important points. Operators, vectors and matrices are denoted in bold, scalars in normal text. Although I have tried to keep the notation as consistent as possible, different branches in computational chemistry often use different symbols for the same quantity. In order to comply with common usage, I have elected sometimes to switch notation between chapters. The second derivative of the energy, for example, is called the force constant k in force field theory, the corresponding matrix is denoted F when discussing vibrations, and called the Hessian H for optimization purposes. [Pg.443]

Tile chloro derivative 33a (not isolated) interacts with pyridine-2,3-diamine in dichloromethane at room temperature to yield 73 (85%) (93BSB357). A further example deals with the reaction between the salt 39 and benzene-1,2-diamine, which gives an imine 74 (80%) under special experimental conditions (93BSB357). In order for the reaction to work, the salt 39 must be isolated prior to its employment (Section IV,C,8). No traces of the diimines were detected for both cases. However, the experimental conditions were not optimized for this purpose since no more than three equivalents of the diamines were used (Scheme 23). [Pg.208]


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