Unimolecular rate theory

If Other fall-off broadening factors arising m unimolecular rate theory can be neglected, the overall dependence of the rate coefficient on pressure or, equivalently, solvent density may be represented by the expression [1, 2]... 

The theory of isolated resonances is well understood and is discussed below. Mies and Krauss [79, ] and Rice [ ] were pioneers m treating unimolecular rate theory in temis of the decomposition of isolated Feshbach resonances. 

Hase W L 1983 Variational unimolecular rate theory Acc. Chem. Res. 16 258-64... 

Mies F H 1969 Resonant scattering theory of association reactions and unimolecular decomposition. Comparison of the collision theory and the absolute rate theory J. Cham. Phys. 51 798-807... 

Hase W L, Cho S-W, Lu D-H and Swamy K N 1989 The role of state specificity in unimolecular rate theory Chem. Phys. 139 1-13... 

Forst, W. Unimolecular rate theory test in thermal reactions, J.Phys.Chem., 76 (1972), 342-348... 

Using unimolecular rate theory, the branching ratio k /k ... 

If the photochemical step is first order (i.e., either uni-molecular or bimolecular where the two reactant molecules are restricted to react only with each other as in a solid state or on a membrane), then we can apply unimolecular rate theory (17) to estimate E... 

Troe, J., Predictive Possibilities of Unimolecular Rate Theory, J. Phys. Chem., 83, 114-126 (1979). 

Calculational estimates of the lifetimes of the trimethylene diradical " based on microcanonical variational unimolecular rate theory and direct dynamics simulations have been reported. The lifetimes derived from theory, 91 and 118 fs, are comparable to the experimental estimate, 120 20 fs. Similar lifetime estimates from theory for tetramethylene are comparable, or slightly below, the experimental value. ... 

G.M. Wieder and R.A. Marcus. Dissociation and Isomerization of Vibrationally Excited Species. II. Unimolecular Reaction Rate Theory and Its Application. J. Chem. Phys., 37 1835-1852,1962. 

Experimental rate constants, kinetic isotope effects and chemical branching ratios for the CF2CFCICH3-do, -d, -d2, and -d2 molecules have been experimentally measured and interpreted using statistical unimolecular reaction rate theory.52 The structural properties of the transition states needed for the theory have been calculated by DFT at the B3PW91 /6-31 G(d,p/) level. 

The most widely accepted theory of unimolecular reactions of polyatomic ions remains the quasiequilibrium theory (QET) [591, 720, 883], which is a treatment in the spirit and tradition of absolute reaction rate theory. Thus it is assumed that the rate of reaction of an ion is slow relative to the rate of energy flow among its vibrational modes and that each reaction may be described as a motion along a reaction coordinate which is separable from all other internal coordinates and which passes through a critical configuration (the transition state ). It is further assumed that ions formed in excited electronic states rapidly redistribute such electronic energy over vibrational levels of the ground electronic state. One further assumption is necessary, and that is that the time involved in the ionization process is short compared with subsequent reaction times. The QET model is taken as the theoretical basis of this review. QET leads to... 

CLASSICAL, SEMICLASSICAL, AND QUANTUM MECHANICAL UNIMOLECULAR REACTION RATE THEORY... 

Rigorous Quantum Rate Theory Versus the Quantized ARRKM Theory A Semiclassical Approximation to the Rigorous Quantum Rate Theory Effective Hamiltonian Approach to Unimolecular Dissociation Wave Packet Dynamics Approach VII. Quantum Transport in Classically Chaotic Systems... 

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