Computational methods stoichiometric analysis

When more than one reactant is present in the rate equation, the isolation method can be used together with the differential method. The isolation method requires the use of one reactant in large excess while the concentration of the isolated reactant is varied in this case, kinetic analysis is conducted in stages using one isolated reactant at a time. However, this method of partial analysis has to be employed with caution in solid-catalyzed reactions since, in certain reactions, a large excess of any one reactant may have an adverse effect on the active sites of the catalyst. Linearized equations of the form presented in Example 2 can easily be handled by the computational methods available even if reactant concentrations are comparable but present in non-stoichiometric proportions ... 

A new scheme for the chemical model determination in equilibria studies might include except statistical tests (1) the application of factor analysis to estimate directly the number of species in solution and (2) the method of direct computation of species stoichiometry via simultaneous calculation of stability constants and stoichiometric indices—the ESI approach. The ESI method might also be used as a new diagnostic tool when searching the best chemical model. The proposed novel scheme of CMD based on PCA and ESI is schematically given in Figure 3.6. 

Poll reported a similar method to synthesize nitrogen-containing heterocycles via it-allyl-palladium intermediate [11]. It was worth noting that when the reaction is conducted in acetic acid rather than in methylene dichloride or terahydro-furan, a strong accelerating effect occurs in direct intramolecular allylic C(sp )-H cyclization (Scheme 2.6). Stoichiometric tests and computational Density Functional Theory analysis of the palladium reoxidation step provided an overview of the structural and energetic role of acetic acid in increasing the efficacy of the entire catalytic cycle (Scheme 2.6). 

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