Basing on the simple model of spin-lattice relaxation used by Afanasev and Kagan [3], we have investigated the modifications of the Mossbauer line shape due to relaxation effects. Utilizing Zwanzig's formalism as in I, we eliminate the bath (lattice) variables and retain only the Hamiltonian for the entire Mossbauer ion in the final formal expressions for the line shape. The essential difference compared to I is that in the present paper the electronic shell of the respective nucleus is included in the quantum mechanical subsystem. Therefore this theory is applicable to all relaxation rates. This has already been pointed out in [3] and is elucidated here by making evident that all results found by the solution of rate equations or by stochastic model treatments are special cases of the present theory.

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The extrema of the position-dependent spontaneous magnetization in a periodically layered twodimensional Ising model are calculated exactly. Their asymptotic behaviour for infinite width of the surrounding homogeneous sublayer is given. The perturbations caused by the neighbouring sublayers on this extremum in a very thick sublayer are shown to be decoupled. Thus the asymptotic decay of the magnetization far from a single layer-shaped inhomogeneity can be inferred from the quoted asymptotics of an extremum, and it is found to be exp( -d/£i) where d is the distance to the inhomogeneity and ff the correlation length in the underlying homogeneous lattice. The connection of this decay law to the asymptotic decay of correlations is dicussed.

Electrical and thermal conductivity and thermoelectric power were theoretically calculated and measured for (La,Gd)Al2—a dilute magnetic alloy with ferromagnetic coupling of the Gd spins to the host electrons—between 0.3 and 10 K, and up to 8 T. It turned out that the transport properties at finite field deviate markedly from the zero-field behavior, e.g., in the electrical resistivity (where a steplike transition is found between the high-temperature logarithmic increase and a low-temperature plateau). A theoretical result for the Hall coefficient is also given

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