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Phonon-assisted reactions concept

Next, we discuss the concept of phonon-assisted reactions. In relation to thermal reactions, they can be assisted by phonon-mode softening leading to large-amplitude overdamped oscillations. In the case of a photochemical reaction, a strong electron-phonon coupling can assist in polymerization. Then some non-linear spectroscopic studies are discussed which illuminate on the dynamics of photopolymerization process. Then follows a discussion of results on reaction in a different kind of molecular assembly, the Langmuir-Blodgett films. Finally, some gas-solid interface reactions which produce polymers in a doped state are discussed. [Pg.107]

Recently, we have Introduced a new concept of phonon-assisted reaction (2). In other words, a reaction In the solid state can be assisted by these low frequency cooperative molecular motions. The concept of the phonon-assisted chemical transformation bears a direct analogy to that of a phonon-assisted physical transformation In solid. Important phonon Interactions can be divided Into two categories (1) Anharmonic phonon-phonon Interactions and (11) electron-phonon Interactions. [Pg.108]

This paper presents studies of solid state polymerization aimed towards formulating a dynamic model of reactivity in the condensed phase. Phonon spectroscopy is successfully used to elucidate the mechanism of lattice control of the reaction. Novel concepts of phonon-assisted thermal and photochemical reactions are introduced, supported by experimental data. Non-linear laser spectroscopy is used to find the importance of biexcitonic processes in photopolymerization. Also, spectroscopic studies of reactions in Langmuir-Blodgett films and at gas-solid interface which produce ordered polymers are presented. [Pg.106]

However it turned out that the structural, chemical and dynamical details are essential for complex descriptions of long-range proton transport. These parameters appear to be distinctly different for different families of compounds, preventing proton conduction processes from being described by a single model or concept as is the case for electron transfer reactions in solutions (described within Marcus theory [23]) or hydrogen diffusion in metals (incoherent phonon assisted tunneling [24]). [Pg.714]


See other pages where Phonon-assisted reactions concept is mentioned: [Pg.108]   
See also in sourсe #XX -- [ Pg.108 , Pg.110 , Pg.111 ]




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