Dynamic intramolecular

Tunnelling has attracted the attention of many chemists and physicists for its importance as a mechanistic pathway in chemical reactions and rearrangements 

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A situation that arises from the intramolecular dynamics of A and completely distinct from apparent non-RRKM behaviour is intrinsic non-RRKM behaviour [9], By this, it is meant that A has a non-random P(t) even if the internal vibrational states of A are prepared randomly. This situation arises when transitions between individual molecular vibrational/rotational states are slower than transitions leading to products. As a result, the vibrational states do not have equal dissociation probabilities. In tenns of classical phase space dynamics, slow transitions between the states occur when the reactant phase space is metrically decomposable [13,14] on the timescale of the imimolecular reaction and there is at least one bottleneck [9] in the molecular phase space other than the one defining the transition state. An intrinsic non-RRKM molecule decays non-exponentially with a time-dependent unimolecular rate constant or exponentially with a rate constant different from that of RRKM theory. 

The above describes the fundamental assumption of RRKM theory regarding the intramolecular dynamics of A. The RRKM expression for k E) is now derived. 

Regardless of the nature of the intramolecular dynamics of the reactant A, there are two constants of the motion in a nnimolecular reaction, i.e. the energy E and the total angular momentum j. The latter ensures the rotational quantum number J is fixed during the nnimolecular reaction and the quantum RRKM rate constant is specified as k E, J). 

Heller E J 1983 The correspondence principle and intramolecular dynamics Faraday Discuss. Cham. Soc. 75 141-53... 

Quack M 1982 The role of intramolecular coupling and relaxation in IR-photochemistry Intramolecular Dynamics, Proc. 15th Jerusalem Symp. on Quantum Chemistry and Biochemistry (Jerusalem, Israel, 29 March-1 April 1982) ed J Jortner and B Pullman (Dordrecht Reidel) pp 371-90... 

Quack M 1990 The role of quantum intramolecular dynamics in unimolecular reactions Phil. Trans. R. Soc. Lond. A 332 203-20... 

Lehmann K K, Scoles G and Pate B FI 1994 Intramolecular dynamics from eigenstate-resolved infrared-spectra A/ / . Rev. Phys. Chem. 45 241 -74... 

Quack M and Suhm M A 1991 Potential energy surfaces, quasiadiabatic channels, rovibrational spectra, and intramolecular dynamics of (HF)2 and its isotopomers from quantum Monte Carlo calculations J. Chem. Phys. 95 28-59... 

Gerber R B, Buch V and Ratner M A 1982 Simplified time-dependent self consistent field approximation for intramolecular dynamics Chem. Phys. Lett. 91 173... 

Lovejoy C M and Nesbitt D J 1989 Intramolecular dynamics of Van der Waals molecules an extended infrared study of Ar-HF J. Chem. Phys. 91 2790-807... 

Experimental studies of liquid crystals have been used for many years to probe the dynamics of these complex molecules [12]. These experiments are usually divided into high and low-frequency spectral regions [80]. This distinction is very important in the study of liquid crystalline phases because, in principle, it can discriminate between inter- and intramolecular dynamics. For many organic materials vibrations above about 150 cm are traditionally assigned to internal vibrations and those below this value to so-called lattice modes . However, the distinction is not absolute and coupling between inter- and intramolecular modes is possible. 

Schwille P, Kummer S, Heikal AA, Moemer WE, Webb WW (2000) Fluorescence correlation spectroscopy reveals fast optical excitation-driven intramolecular dynamics of yellow fluorescent proteins. Proc Natl Acad Sci USA 97 151-156... 

Haas, E. and Steinberg, I. (1984). Intramolecular dynamics of chain molecules monitored by fluctuations in efficiency of excitation energy transfer. Biophys. J. 46, 429-37. 

The interactions of (212) and related species with monovalent and divalent metal cations have been studied by nmr spectroscopy (Lehn Simon, 1977). The study indicated that sequential formation of mono-and di-cation complexes occurs (see [4.7]). These studies, and especially a 13C nmr study of the 1 1 complex of (212) with barium nitrate, suggest that the 1 1 species are unsymmetrical with the metal ion being contained in one of the azacrown cavities. Nevertheless, the nmr data also indicate that these 1 1 species undergo internal cation exchange between the respective azacrown sites. This intramolecular dynamic behaviour serves... 

R2SnCl2 +F RSnCl3 + F (R = Ph, Me, n-Bu, f-Bu) 19F and 119Sn NMR. Intermolecular and intramolecular dynamics of a CH2C12 solution of chlorinated organotin compounds and fluoride ions lead to multiple replacement reactions. Complex ions such as [Ph2SnCl3-KFn], n = 1-3 are formed, that are stereochemically rigid at —100 °C and fluxional at — 80 °C. 159... 

Jortner, J. and Pullman, B.(ed.), Intramolecular dynamics, The Jerusalem Symposia on Quantum Chemistry and Biochemistry, Reidel, Dordrecht, 1982. 

Intramolecular Dynamics from Eigenstate-Resolved Infrared Spectra. 

Levine, R. D. (1982), Algebraic Approach to Molecular Stmcture and Dynamics, in Intramolecular Dynamics, J. Jortner and B. Pullman (eds.), Reidel, The Netherlands. 

Reddy, K. V., Heller, D. F., and Berry, M. J. (1982), Highly Vibrationally Excited Benzene Overtone Spectroscopy and Intramolecular Dynamics of CsH6, C6D6, and Partially Deuterated or Substituted Benzenes, J. Chem. Phys. 76, 2814. 

At present, three main approaches to the analysis of intramolecular dynamics in proteins based on fluorescence studies are most commonly used (Figure 2.3).( 4)... 

The elucidation of the intramolecular dynamics of tryptophan residues became possible due to anisotropy studies with nanosecond time resolution. Two approaches have been taken direct observation of the anisotropy kinetics on the nanosecond time scale using time-resolved(28) or frequency-domain fluorometry, and studies of steady-state anisotropy for xFvarying within wide ranges (lifetime-resolved anisotropy). The latter approach involves the application of collisional quenchers, oxygen(29,71) or acrylamide.(30) The shortening of xF by the quencher decreases the mean time available for rotations of aromatic groups prior to emission. 

K. K. Turoverov and I. M. Kuznetsova, Polarization of intrinsic fluorescence of proteins. 2. The studies of intramolecular dynamics of tryptophan residues, Mol. Biol. (Moscow) 17, 468-475 (1983). 

PHOTOINDUCED BOND CLEAVAGE AS A PROBE OF MODE SPECIFICITY AND INTRAMOLECULAR DYNAMICS IN ROVIBRATIONALLY EXCITED TRIATOMIC TO 10 ATOM MOLECULES... 

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