Exchange indirect

The content of the material in a carbon reservoir is a measure of that reservoir s direct or indirect exchange rate with the atmosphere, although variations in solar also create variations in atmospheric content activity (Stuiver and Quay, 1980, 1981). Geologically important reservoirs (i.e., carbonate rocks and fossil carbon) contain no radiocarbon because the turnover times of these reservoirs are much longer than the isotope s half-life. The distribution of is used in studies of ocean circulation, soil sciences, and studies of the terrestrial biosphere. 

The canonical spin glass consists of a noble metal (Au, Ag, Cu, or Pt) diluted with a transition metal ion, such as Fe or Mn. The magnetic interaction in such systems is mediated by the conduction electrons, leading to an indirect exchange interaction—the RKKY (Ruderman and Kittel [70], Kasuya [71], and Yosida [72]) interaction, whose coupling constant J R) oscillates strongly with distance r between the spins as... 

Indirect Exchange Rates. In this case, the line shape is indirectly related to the acid-base equilibrium. Besides measuring intermolecular processes like the proton exchange rates, DNMR often has been used to measure intramolecular processes like conformational changes that occur on the same time scale. When the activation energy of such a process is very different in the acidic and basic forms for an indicator, DNMR can be used to measure the ionization ratio. 

In the case of chemisorption the direct exchange repulsion between the closely positioned adspecies may takes place, which decreases exponentially with the distance. There are also reports on the existence of an indirect exchange adspecies interaction through the solid s conduction electrons [70,71]. At great interadspecies distances the energy of this interaction is described as follows ... 

Figure 3 Defects and associated diffusion mechanism 1 and 2, diffusion mechanism by direct exchange 3, diffusion through vacancy 4, direct interstitial mechanism 5, indirect interstitial or caterpillar mechanism 6, Frenkel defect 7, indirect exchange 8, Schottky defect. (Ref 9. Reproduced by permission of Cambridge University Press)...

Indirect exchange exchange coupling between electrons on centers that require the orbitals of an intermediate group or groups for the process to occur... 

The compound Tl2Tc3 is a p-type semiconductor in which the thallium atoms are located in channels between puckered Te layers. A ° T1 and jvjmr study of this material has revealed that significant indirect exchange coupling occurs between the nuclei by overlap of the thallium electron wave functions, mainly across the Te atoms. Good agreement was found between the NMR conclusions and the calculated electronic stmcture and density of states in this semiconductor (Panich and Doert 2(XX)). 

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