Crystal field level scheme

Temple and McEwen (1977) have evaluated the temperature dependence of Tr (PQ) for Pr, using the crystal field level scheme shown in fig. 6.17. In the absence of detailed information about the Fermi surface, po was determined by fitting the calculation to experimental data (after subtraction of the residual resistance) at 10 K, where the phonon contribution is much smaller than the magnetic contribution. As indicated by fig. 6.40, the spin-disorder resistivity has almost... 

Obviously a measurement of the crystal-field energy levels has to employ different experimental methods in a salt and in a metal. For example the important techniques of optical absorption and fluorescence which are used for the RE-salts cannot be used for the metals. Mainly for that reason crystal-field level schemes in metals have been investigated only recently in considerable detail. We will list in the following some experimental methods which can be applied to metals and we will leave out the optical methods since they have been extensively covered for example by Wybourne (1965) and Dieke (1968). 

In the following we will refer to this particular interaction. The eqs. (17.68) can be solved numerically for a given crystal-field level scheme and a given electron-RE-ion interaction. In fig. 17.16 we show the results for a two singlet system for various different ratios S/Tco. 

Fig. 88. The magnetic contribution to the resistivity normalized to p ,(200 K) as a function of temperature for PrCu, (Takayanagi 1984). The solid curve is calculated using the crystal-field level scheme of Pr taken from Goremychkin et al. (1988).

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