Compositional dependent coordination

The polyisoprenes prepared in strongly polar solvents, such as ethers, have a mixed isomeric composition. The composition depends on solvent as well as on initiator. Tobolsky and Rogers (1959) found that the predominate isomers are those from 3,4 and tmns-1,4 additions. If weakly coordinating solvents are used. 

Studies of temperatme, pressme and composition dependencies of various properties of systems or of individual phases show that the coordinates of a phase transformation will become apparent as a change in the slope of the property curve against one of the variables. 

Equation (61) makes allowance for differences in the genesis of ternary contacts but it does not yet consider that the number of segments of the third component in the coordination sphere of a certain binary contact might deviate from that expected from the average composition due to very favorable or unfavorable interactiOTis (quasi chemical equilibria). One way to model such effects consists of the introduction of composition-dependent ternary interaction parameters, as formulated in the following equation ... 

The atmospheric corrosion rate is influenced by many parameters, one of the most important being the formation and protective ability of the corrosion products formed. The composition of the corrosion products depends on the participating dissolved metal ions and the access to anions dissolved in the aqueous layer. The eventual thickening of the film of corrosion products can be described in a sequence of consecutive steps—dissolution-coordination-reprecipitation—where the dissolution step is acid dependent, coordination is based on the HSAB principle, and reprecipitation depends on the activities of the species involved. 

The core composition of A and B atoms in the fee nanoparticles with various shapes can be estimated by Eqs. (9.25) and (9.26), and needs to be obtained from the experimental total average coordination number (K) associated with the fee model calculation considering various shapes. In general, the surface composition depends only on the structure of the nanoparticles, while core composition relies not only on the structure, but also on the shape of the nanoparticles. 

Figure 5.11 reproduces the results of the curve-fitting carried out in the FT-Raman SjCFs/v SNS band of LiTFSI-doped di-ureasils and the composition dependence of the area of the resolved components, respectively. At n > 40 the band was decomposed into a single component at 739 cm" due to free TFSI" ions, ° whereas at n = 20 it was resolved into two peaks at 743 and 739 cm". The former component is ascribed to the occurrence of contact ion pairs. Figure 5.11(b) shows that, while the concentrations of free anions and coordinated anions remain essentially constant at 40 < n < 8, at n = 5 the fraction of free anions decreases significantly and the proportion of associated species increases concomitantly. 

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