Gamow model

Electrons that transfer are loosely bound valence electrons. If we use p = 1 A, the ET rate decreases by a factor of e 2.72 per A. If the distance is 3 A, the rate decreases by e 20. Eor every 3 A increase in the distance between D and A, the rate thus decreases by a factor of 20. For a distance of 15 A, the decrease factor is consequently 20 = 3.2 x 10 . Such a low tunneling rate is usually fully acceptable in a biological system. Only the charge separation process requires a million times faster rate. The chlorophyll units exchanging electrons are therefore in close contact with each other. 

Unfortunately, the Gamow model is incapable of accounting for chemical structure. Is the function of distance always exponential or are other mechanisms possible  

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A theoretical model of the low-temperature decay of etr in MTHF discovered in ref. 30 was suggested in ref. 31. According to this model, the disappearance of et in y-irradiated MTHF at 77 K is due to electron tunneling from a trap to a hole centre. The form of the potential barrier for electron tunneling used in ref. 31 to analyze the curves of the decay of etr is represented schematically in Fig. 9(a). To evaluate the probability of tunneling per unit of time, the Gamow formula... 

Examples of large-basis shell-model calculations of Gamow-Teller 6-decay properties of specific interest in the astrophysical s-and r- processes are presented. Numerical results are given for i) the GT-matrix elements for the excited state decays of the unstable s-process nucleus "Tc and ii) the GT-strength function for the neutron-rich nucleus 130Cd, which lies on the r-process path. The results are discussed in conjunction with the astrophysics problems. 

For the nuclei studied in this experiment the dominant decay mode is Gamow-Teller beta decay.Partial halflives corresponding to Gamow-Teller beta decay calculated in a spherical shell model formalism [Bro85] are shown in Table I.The calculated lifetimes are with one exception(17C) all shorter than the measured lifetimes. 

Weizsacker s theory shared with other theories of element formation the assumption of an equilibrium mechanism. It was the abandonment of this assumption in the 1940s that paved the way for the first successful big-bang model of the universe, proposed by George Gamow and his collaborators in 1948. That the equilibrium hypothesis might not be tenable had been suggested as early as 1931, when the two American chemists Harold Urey and Charles Bradley argued that the relative abundance of terrestrial elements could not be reconciled with the hypothesis, whatever the temperature of the equilibrium mixture. [45]... 

THIRTY YEARS THAT SHOOK PHYSICS The Story of Quantum Theory, George Gamow. Lucid, accessible introduction to influential theory of energy and matter. Careful explanations of Dirac s anti-particles, Bohr s model of the atom, much more. 12 plates. Numerous drawings. 240pp. 5X x 8H. 24895-X Pa. 5.95... 

This contradiction was explained by Gamow, and independently by Gurney and Condon, in 1928, by using a quantum mechanical model, which retained the feature of the "one-body model" with a preformed a-particle inside the nuclear potential wall of even-even nuclei. 

The notion of complex energies in quantum physics was introduced ad hoc, via a simple model, by Gamow [25], soon after the establishment of fhe well-known Hilbert-space QM developed for the discrete spectra. This notion was in radical departure from fhe Hermitian character of QM, whose normal... 

Two decades after the exponential decay theories of Gamow, and Weisskopf and Wigner, Hellund [52] showed that decay could not be exactly exponential and that it should be slower at long times. Later on, Hohler, going beyond the simplifications of the Weisskopf-Wigner model, obtained a power law for long times [53] see also Ref. [54]. 

George Gamow had proposed such a model in Copenhagen in 1928. Bohr credited it to Gamow at the October 1933 Solvay conference, as did Heisenberg. Bohr and his student Fritz Kalkar subsequently developed the model and physicists customarily attribute it to him. 

The textbook tunneling model was originally invented by Gamow. Exponential decrease of rate with distance is obtained. This model cannot be used in proteins... 

The states [ ) and their duals (model space. The imaginary part of the complex energy Si — Ei irj/2 is negative. The non-orthogonal projectors (f>i) i enable to turn the... 

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