Energy transfer, intramolecular

The transfer of electronic energy (and excitation) between two different molecules (intermolecular energy transfer pathway iv of Fig. 1) or between two different electronic states (intramolecular energy transfer pathway v) plays a central role in photochemistry. The equivalent processes involving electrons, in which charge is transferred to a different molecule, or is moved in position in one molecule, may also be promoted photochemically. These processes are explored in the present section. 

The rate of spin-forbidden transitions may be perturbed by the external environment. Such an influence is seen in the effects of the addition 

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In this chapter we shall first outline the basic concepts of the various mechanisms for energy redistribution, followed by a very brief overview of collisional intennoleciilar energy transfer in chemical reaction systems. The main part of this chapter deals with true intramolecular energy transfer in polyatomic molecules, which is a topic of particular current importance. Stress is placed on basic ideas and concepts. It is not the aim of this chapter to review in detail the vast literature on this topic we refer to some of the key reviews and books [U, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, and 32] and the literature cited therein. These cover a variety of aspects of tire topic and fiirther, more detailed references will be given tliroiighoiit this review. We should mention here the energy transfer processes, which are of fiindamental importance but are beyond the scope of this review, such as electronic energy transfer by mechanisms of the Forster type [33, 34] and related processes. 

A 3.13.2 BASIC CONCEPTS FOR INTER- AND INTRAMOLECULAR ENERGY TRANSFER... 

Figure A3.13.1. Schematic energy level diagram and relationship between mtemiolecular (collisional or radiative) and intramolecular energy transfer between states of isolated molecules. The fat horizontal bars indicate diin energy shells of nearly degenerate states.

A 3.13.4 INTRAMOLECULAR ENERGY TRANSFER STUDIES IN POLYATOMIC MOLECULES... 

Marcus R A 1983 On the theory of intramolecular energy transfer Faraday Discuss. Chem. Soc. 75 103-15... 

For the case of intramolecular energy transfer from excited vibrational states, a mixed quantum-classical treatment was given by Gerber et al. already in 1982 [101]. These authors used a time-dependent self-consistent field (TDSCF) approximation. In the classical limit of TDSCF averages over wave functions are replaced by averages over bundles of trajectories, each obtained by SCF methods. 

Gerber, R.B., Buch, V., Ratner, M.A. Time-dependent self-consistent field approximation for intramolecular energy transfer. I. Formulation and application to dissociation of van der Waals molecules. J. Chem. Phys. 77 (1982) 3022-3030. 

Extrusion or elimination of small stable species such as CO2 Intramolecular energy transfer Quenching involving translational or vibrational excitation of another molecule... 

Irradiation of solutions containing equimolar amounts of n = 1-4 and /ra/is-j9-methylstyrene as a quencher at concentrations comparable to those of the experiments reported in Table 6.6 indicated that intermolecular energy transfer cannot compete with intramolecular energy transfer under these conditions. 

Dale, R., Eisinger, J. and Blumberg, W. (1979). The orientational freedom of molecular probes. The orientation factor in intramolecular energy transfer. Biophys. J. 26, 161-94. 

E. Intramolecular Energy Transfer in Luminol-Type Hydrazide... 

It was concluded, therefore, that intramolecular energy transfer is involved in the chemiluminescence of 58. The rate of energy transfer was calculated to be 2.3 X 107 sec-1 12 ). 

Figure 3 Different processes for losing energy from the excited state (1) direct CL (2) molecular dissociation (3) chemical reaction with other species (4) intramolecular energy transfer (5) intermolecular energy transfer (in case of a fluorophore, indirect CL) (6) isomerization (7) physical quenching. (Adapted from Ref. 1.)...

Davis, M. J. Bottlenecks to intramolecular energy transfer and the calculation of relaxation rates, J. Chem. Phys., 83 (1985), 1016-1031... 

Both RRGM and SLP have been used to compute various transition amplitudes with high efficiency and accuracy. Their applications, which have been reviewed in the literature,56 57 59 include laser-molecule interaction,43 44 99 correlation functions,45 104 absorption and emission spectra,100 103 105-107 intramolecular energy transfer,108-115 vibrational assignment,103 116 117 and reaction dynamics. ... 

M. Farnik and D. J. Nesbitt, Intramolecular energy transfer between oriented chromophores High resolution infrared spectroscopy of HCltrimer. / Chem. Phys. 121, 12386 12395 (2004). 

O. V. Boyarkin, T. R. Rizzo, and D. S. Perry, Intramolecular energy transfer in highly vibrationally excited methanol. II. Multiple time scales of energy redistribution. J. Chem. Phys. 110, 11346 11358 (1999). 

The probability of intramolecular energy transfer between two electronic states is inversely proportional to the energy gap, AE, between the two states. The value of the rate constant for radiationless transitions decreases with the size of the energy gap between the initial and final electronic states involved. This law readily provides us with a simple explanation of Kasha s rule and Vavilov s rule. 

Ziessel R, Goze C, Ulrich G, Cesario M, Retailleau P, Harriman A, Rostron JP (2005) Intramolecular energy transfer in pyrene-bodipy molecular dyads and triads. Chemistry 11 7366-78... 

Dale R. E., Eisinger J. and Blumberg W. E. (1975) The Orientational Freedom of Molecular Probes. The Orientation Factor in Intramolecular Energy Transfer, Biophys. J. 26, 161-194. 

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