Pairing transition

Calculations of the composition (112/ns) of symmetric nuclear matter (np = nn, no Coulomb interaction) are shown in Fig. 3 [7], At low densities, the contribution of bound states becomes dominant at low temperatures. At fixed temperature, the contribution of the correlated density 112 is first increasing with increasing density according to the mass action law, but above the Mott line it is sharply decreasing, so that near nuclear matter density (ns = ntot = 0.17 fm-3) the contribution of the correlated density almost vanishes. Also, the critical temperature for the pairing transition is shown. 

An alternate mechanism invoking an ion-pair transition-state assembly has been proposed to account for the enantioselectivity of the asymmetric epoxidation process [137]. In this proposal, two additional alcohol species are required in the transition-state complex. This... 

Figure 3.16 Energy level diagram for ferric iron matched to spin-forbidden crystal field transitions within Fe3+ ions, which are portrayed by the polarized absorption spectra of yellow sapphire (adapted from Ferguson Fielding, 1972 Sherman, 1985a). Note that the unassigned band at -17,600 cm-1 represents a paired transition within magnetically coupled Fe3+ ions located in adjacent face-shared octahedra in the corundum structure.

Shock-wave experiments causing phase changes in wiistite, Fe094O, and Fe203 have also produced controversial evidence for spin-pairing transitions in iron cations (Jeanloz and Ahrens, 1980 Jackson and Ringwood, 1981 Goto et al., 1982 Syono etal., 1984). 

Calculated spin-pairing transition pressures in the Mantle... 

Goto, T., Sato, J. Syono, Y. (1982) Shock-induced spin-pairing transition in Fe203 due to the pressure effect on the crystal field. In High-Pressure Research in Geophysics. (S. Akimoto M. H. Manghani, eds D. Reidel Publ. Co., Dortrecht), pp. 595-609. 

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