Transfer of Vibrational Energy

Rice S A 1981 An overview of the dynamics of intramolecular transfer of vibrational energy Adv. Chem. Phys. 47 117-200... 

Sharma R D and Brau C A 1969 Energy transfer in near-resonant molecular collisions due to long-range forces with application to transfer of vibrational energy from the mode of CO2 to N2 J. Chem. Phys. 50 924-30... 

Conduction. In a solid, the flow of heat by conduction is the result of the transfer of vibrational energy from one molecule to another, and in fluids it occurs in addition as a result of the transfer of kinetic energy. Heat transfer by conduction may also arise from the movement of free electrons, a process which is particularly important with metals and accounts for their high thermal conductivities. 

Rice, S. A. (1981), Overview of the Dynamics of Intramolecular Transfer of Vibrational Energy, Adv. Chem. Phys. 47, 117. 

Internal Conversion.—Nonradiative transition between states of like multiplicity. The process is conceived of as involving iso-energetic transitions from a higher electronic state to an upper vibrational level of a lower state (cf. Fig. 1). To consummate the change, transfer of vibrational energy to the environment (external conversion) must occur rapidly. Since some authors feel that the transition between states in solution is directly coupled with solvent phonon states, the distinction... 

Energy Transfer—(Excitation transfer).— As used in photochemistry the term is nonspecific and refers to any transfer of energy from an excited molecule to other species. The energy acceptor may itself be promoted to an excited electronic state or the electronic energy may be donated to a host system as vibrational, rotational or translational energy. The term is used to describe variously overall processes which may involve two or more steps (e.g., internal conversion followed by transfer of vibrational energy) and the individual steps in which the energy passes from one molecule to another (or others). 

From the slopes of plots of pentenal/CO vs. pressure of added gas, the relative efficiencies of the inert gas molecules for transfer of vibrational energy are obtained. These are shown in Table III. These relative values seem to follow the same order as the efficiencies of the same molecules in the thermal decomposition of cyclopropane and cyclobutane. 

Perhaps the first significant experiments on transfer of vibrational energy were performed in Norrish s laboratory at Cambridge29. When chlorine dioxide is exposed to radiation of the appropriate wavelength it dissociates... 

Woutersen S, Bakker HJ. 1999. Resonant intermolecular transfer of vibrational energy in liquid water. Nature 402 507-509. 

The above considerations indicate that at some intermediate value of r, the I2 system on its way to form the completely equilibrated ground state will experience a significant charge flow, as charge localized l2 converts to charge-delocalized I2. Associated with this shift is a corresponding force that potentially can be quite effective in the transfer of vibrational energy. 

Conduction is the most widely understood mechanism of heat transfer and the main method in solids. The flow of heat depends upon the transfer of vibrational energy from one molecule to another and, in the case of metals, the movement of free electrons. Radiation is rare in solids but examples are found among glasses and plastics. Convection by definition, is not possible under these conditions. Conduction in the bulk of fluids is normally overshadowed by convection, but it assumes great importance at fluid boundaries. 

Although the Lindemann theory is often satisfactory, it is incomplete since it does not fully recognise the relation between translational and internal energies. In many reactions the rate of activation by collision is not itself explicable unless it is assumed that activation can also occur by the transfer of vibrational energy from one molecule to another. This possibility was recognised by Hinshelwood and by Lewis and may be equivalent, in effect, to multiplying the frequency factor by 10" or more. 

Very little is known about the transfer of vibrational energy from one molecule to another, but for dissimilar species such as oxygen and ozone it would be expected to be very inefficiently transferred in such large amounts as would be required for an energy chain. It seems much more reasonable to expect vibrationally excited oxygen molecules to lose their energy preferentially in collision with other oxygen molecules... 

E.E.Nikitin, Transfer of vibrational energy in collision of diatomic molecules. Proceedings of Institute of Mechanics, Moscow State University 24,44 (1973)... 

This article deals with a field of research on the borderline between physical chemistry and laser physics. As it is intended to combine aspects of both areas, molecular amplifiers based on partial or total vibrational inversion are first characterized in general, after which the generation, storage, distribution, and transfer of vibrational energy in chemical processes is reviewed. There is a brief discussion of the experimental requirements for laser oscillation and associated hardware problems. Experimental results for specific chemical laser systems are then surveyed and the prospects for high-power chemical laser operation considered. The concluding sections are devoted to the contribution of chemical lasers to reaction kinetics and their other uses in chemistry. 

So far we have considered internal motions mostly of isolated molecules, not interacting with an environment. This condition will be approximately met in a dilute gas. However, many of the issues raised may be of relevance in processes where the molecule is not isolated at all. An example already briefly noted is the transfer of vibrational energy from a molecule to a surrounding bath, for example a liquid. It has been found... 

S. A. Rice, Overview of the dynamics of intramolecular transfer of vibrational energy, Adv. Chem. Phys. 47 117 (1981) P. Brumer, Intramolecular energy transfer theory for the onset of statistical behavior, Adv. Chem. Phys. 47 202 (1981) P. Brumer and M. Shapiro, Chaos and reaction dynamics, Adv. Chem. Phys. 70 365 (1988). 

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