Strong interactions model

The three-phase multi-species framework follows the strongly interacting model of [1], namely ... 

This chapter summarizes the thermodynamics of multicomponent polymer systems, with special emphasis on polymer blends and mixtures. After a brief introduction of the relevant thermodynamic principles - laws of thermodynamics, definitions, and interrelations of thermodynamic variables and potentials - selected theories of liquid and polymer mixtures are provided Specifically, both lattice theories (such as the Hory-Huggins model. Equation of State theories, and the gas-lattice models) and ojf-lattice theories (such as the strong interaction model, heat of mixing approaches, and solubility parameter models) are discussed and compared. Model parameters are also tabulated for the each theory for common or representative polymer blends. In the second half of this chapter, the thermodynamics of phase separation are discussed, and experimental methods - for determining phase diagrams or for quantifying the theoretical model parameters - are mentioned. 

Christine, J.TL. and David, M.T (1991) Heats of mixing of strongly interacting model compounds and miscibility of the corresponding polymers. Macromolecules, 24, 4310-4321. 

Several other equation-of-state models have been proposed The lattice-fluid theory of Sanchez and Lacombe (1978), the gas-lattice model proposed by Koningsveld (1987), the strong interaction model proposed by Walker and Vause (1982), and the group contribution theory proposed by Holten-Anderson (1992), etc. These theories are reviewed by Miles and Rostami (1992) and Boyd and Phillips (1993). The lattice-fluid theory of Sanchez and Lacombe has similarities with the Flory-Huggins theory. It deals with a lattice, but with the difference from the Flory—Huggins model in that it allows vacancies in the lattice. The lattice is compressible. This theory is capable of describing both UCST and LCST behaviour. 

In a regime of strong interaction between the chains no optical coupling between the ground slate and the lowest excited state occurs. The absence of coupling, however, has a different origin. Indeed, below 7 A, the LCAO coefficients start to delocalize over the two chains and the wavefunclions become entirely symmetric below 5 A due to an efficient exchange of electrons between the chains. This delocalization of the wavcfunclion is not taken into account in the molecular exciton model, which therefore becomes unreliable at short chain separations. Analysis of the one-electron structure of the complexes indicates that the... 

In the previous Sections (2.1-2.3) we summarized the experimental and computational results concerning on the size-dependent electronic structure of nanoparticles supported by more or less inert (carbon or oxide) and strongly interacting (metallic) substrates. In the following sections the (usually qualitative) models will be discussed in detail, which were developed to interpret the observed data. The emphasis will be placed on systems prepared on inert supports, since - as it was described in Section 2.3 - the behavior of metal adatoms or adlayers on metallic substrates can be understood in terms of charge transfer processes. 

However, a closer inspection of the experimental data reveals several differences. For ion-transfer reactions the transfer coefficient a can take on any value between zero and one, and varies with temperature in many cases. For outer-sphere electron-transfer reactions the transfer coefficient is always close to 1/2, and is independent of temperature. The behavior of electron-transfer reactions could be explained by the theory presented in Chapter 6, but this theory - at least in the form we have presented it - does not apply to ion transfer. It can, in fact, be extended into a model that encompasses both types of reactions [7], though not proton-transfer reactions, which are special because of the strong interaction of the proton with water and because of its small mass. 

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