Murrell mechanism

The transition dipole mn in Eqs. [136] and [139] is the gas-phase adiabatic transition dipole. Therefore, emission intensities measured in different solvents should generate invariant transition dipoles when treated according to Eqs. [136] and [139]. A deviation from invariance can be used as an indication of the breakdown of the two-state approximation and the existence of intensity borrowing from other excited states of the chromophores (the Murrell mechanism T88,94j Figure 16 illustrates the difference between Eq. [139] and... 

Fame G (1986) Principles of Isotope Geology, Second Edition. John Wiley and Sons, New York Fleischer RL, Raabe OG (1975) Recoiling alpha-emitting nuclei. Mechanisms for uranium-series disequilibrium. Geochim Cosmochim Acta 42 973-978 Goldstein SJ, Murrell MT, Williams RW (1993) Pa and h chronology of mid-ocean ridge basalts. Earth Planet Sci Lett 115 151-159... 

Sims, K.W.W., DePaolo, D.J., Murrell, M.T., Baldridge, W.S., Goldstein, S.J. and Clague, D.A., 1995. Mechanisms of magma generation beneath Hawaii and mid-ocean ridges Uranium/thorium and samarium/neodymium isotopic evidence. Science, 267 508-512. 

The theoretical difficulty of making this separation derives from the indistinguish-ability of electrons and the requirement that the total wavefunction be antisymmetric with respect to permutations of the electronic co-ordinates. One approach has been to abandon a full quantum mechanical description in favour of a simplified model hamiltonian which can be conveniently parameterized in terms of experimental quantities. This is the rationale behind Huckel theory, CNDO, and other more sophisticated methods such as MINDO. These techniques have been well documented and reviewed elsewhere (Dewar,1 Pariser, Parr, and Pople,2 Murrell and Hargett,3 etc.) and will not be pursued further here. 

Jordan, S.L., I.R. McDonald, A.J. Kraczkiewicz-Dowjat, D.P. Kelly, F.A. Rainey, J-.C. Murrell, and A.P. Wood. 1997. Autotrophic growth on carbon disulfide is a property of novel strains of Paracoccus denitrificans. Arch. Microbiol. 168 225-236. Joshi-Tope, G. and A.J. Francis. 1995. Mechanisms of biodegradation of metal-citrate complexes by Pseudomonas fluorescens. J. Bacteriol. 177 1989-1993. 

Konn, D.O., Murrell, J., Despeyroux, D., Gaskell, S.J. (2005) Comparison of the Effects of Ionization Mechanism, Analyte Concentration, and Ion Cool-times on the Internal Energies of Peptide Ions Produced by Electrospray and Atmospheric Pressure Matrix-assisted Laser Desorption Ionization. J. Am. Soc. Mass Spectrom. 16 743-751. 

Table 1.4 lists calculation data on activation and thermodynamic parameters as well as kinetic isotopic effects for three reactions of the retroene type. In the first stage, a search for the transition state structure was conducted and its compatibility with the demands of the Murrell-Laidler theorem verified. Afterwards the vibration frequencies of the reactants and the transition state structure were calculated whose values were used in the corresponding equations. Underestimation of the kinetic isotopic effect in the last two reactions is related to underestimation of the role of the tunnel mechanism (see Sect. 1.5). An exact reproduction of the values of kinetic isotopic effects is a more reliable check on the accuracy of the calculated transition state structures than that of the values of activation entropies. This is explained by the fact that the calculated values of normal vibration frequencies, corresponding to the negative force constants, are directly included into Eqs. (1.24)-(1.26) that determine the magnitude of the kinetic isotopic effect. 

S. Erkoc, J, N. Murrell, and D. C. Clary, Quantum mechanical calculation of collinear atom-triatom transition probabilities for anharmonic triatom potentials, Chem. Phys. Lett. 72 624 (1980). 

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