Quantum tunneling reactions

This relationship is the analogue of the BPS rule for tunneling reactions. The quantum symmetry coefficient a, = — d nk /dAE is greater than and it may exceed 1. 

Quantum tunnelling in chemical reactions can be visualised in terms of a reaction coordinate diagram (Figure 2.4). As we have seen, classical transitions are achieved by thermal activation - nuclear (i.e. atomic position) displacement along the R curve distorts the geometry so that the... 

Ionic dissociation of carbon-carbon a-bonds in hydrocarbons and the formation of authentic hydrocarbon salts, 30, 173 Ionization potentials, 4, 31 Ion-pairing effects in carbanion reactions, 15, 153 Ions, organic, charge density-NMR chemical shift correlations, 11, 125 Isomerization, permutational, of pentavalent phosphorus compounds, 9, 25 Isotope effects and quantum tunneling in enzyme-catalyzed hydrogen transfer. 

Quantum tunneling in chemical reactions 28 Quantum tunneling in solution reactions 29... 

Quantum tunneling in enzyme-catalyzed reactions early indications 35 The rule of the geometric mean ( no isotope effects on isotope effects ) The Swain-Schaad relationship 36... 

Secondary isotope effects measure transition-state structure 37 Quantum tunneling in enzyme-catalyzed reactions breakthroughs 42 Experimental phenomenology of quantum tunneling in enzyme-catalyzed... 

QUANTUM TUNNELING IN ENZYME-CATALYZED REACTIONS EARLY INDICATIONS... 

Experimental phenomenology of quantum tunneling in enzyme-catalyzed reactions... 

Kinetic complexity definition, 43 Klinman s approach, 46 Kinetic isotope effects, 28 for 2,4,6-collidine, 31 a-secondary, 35 and coupled motion, 35, 40 in enzyme-catalyzed reactions, 35 as indicators of quantum tunneling, 70 in multistep enzymatic reactions, 44-45 normal temperature dependence, 37 Northrop notation, 45 Northrop s method of calculation, 55 rule of geometric mean, 36 secondary effects and transition state, 37 semiclassical treatment for hydrogen transfer,... 

Carpenter BK. In Allemann RK, Scrutton NS, editors. Quantum tunnelling in enzyme catalysed reactions. Cambridge RSC Publishing 2009. Chapter 1. 

If the donor has the vibrational quantum numbers ndl and ndf prior to and after the electron tunneling reaction then from eqn. (62) it follows that the transition matrix element is proportional to the multiplier a expC-y B). Employing this fact and using eqns. (63) and (64), Ivanov and Kozhushner [27] represent the probability of tunneling in the form... 

Fig. 9. The effect [26] of the concentration of CC14 on the order, n, of the electron phototransfer reactions from (a) naphthalene and (b) diphenylamine to CC14 with respect to light intensity and (c) schematic representation of the two-quantum over barrier and the one-quantum tunnel electron phototransfer from a donor to an acceptor.

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