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Static electrical and magnetic properties of single crystal ${\mathrm{BaVS}}_{3}$ were measured over the structural ${(T}_{S}=240\mathrm{K}),$ metal insulator ${(T}_{\mathrm{MI}}=69\mathrm{K}),$ and suspected orbital ordering ${(T}_{X}=30\mathrm{K})$ transitions. The resistivity is almost isotropic both in the metallic and insulating states. An anomaly in the magnetic anisotropy at ${T}_{X}$ signals a phase transition to an ordered low-T state. The results are interpreted in terms of orbital ordering and spin pairing within the lowest crystal-field quasidoublet. The disordered insulator at ${T}_{X}lTl{T}_{\mathrm{MI}}$ is described as a classical liquid of nonmagnetic pairs.

The magnetic anisotropy measurements of metallic Y-Ba-Cu-O compounds in the normal phase reveal a temperature-dependent diamagnetic component of the susceptibility that increases with decreasing temperature. The temperature variation of the susceptibility anisotropy and its total change do not seem to be much affected by the presence of the superconductivity at some lower temperature and could not be accounted for by superconducting fluctuations. Rather, the data remind one of the behavior of some quasi-two-dimensional metals with anisotropic Fermi surfaces, reflecting the properties of the low-energy excitations in the normal phase. The anisotropy measurements above the bulk superconducting transition temperature ${\mathit{T}}_{\mathit{c}}$ reveal the nonlinear effects, which are due to the onset of superconductivity in disconnected grains. The existence of a two-step transition, typical for granular superconductors, should be taken into consideration if the normal-phase susceptibility data are compared with the theoretical predictions in the vicinity of ${\mathit{T}}_{\mathit{c}}$.

From a comprehensive study of the magnetic properties of amorphous and liquid Ni100-xBx alloys with 18.5less than or equal toxless than or equal to40, the individual contributions to the magnetization are identified and determined separately. The matrix of the amorphous Ni-B alloys is found to exhibit Pauli paramagnetism even for x=18.5, where the observed magnetization was dominated by superparamagnetic particles. The Pauli susceptibility decreases monotonically with increasing B-content and, for a given composition, it agrees well with extrapolated room-temperature liquid state data and with the value of the corresponding crystalline stoichiometric compound. The critical concentration for the onset of spontaneous magnetic order is established to be more than 81.5-at. % Ni. On the basis of the electronic density of states (DOS) deduced from previous low-temperature specific-heat measurements for various Ni-metalloid alloys, the Stoner-enhanced Pauli susceptibility is calculated for the Ni-B system and a good agreement with the experimental conduction electron susceptibility is obtained. The temperature dependence of the Pauli susceptibility is also discussed for amorphous Ni-B alloys and for liquid Ni-metalloid alloys, the features being explained in terms of the DOS data.

The magnetic susceptibility and susceptibility anisotropy of the quasibinary alloy system ${\mathrm{Ce}}_{x}{\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Cu}}_{2.05}{\mathrm{Si}}_{2}$ have been studied for low concentration of Ce ions. The single-ion description is found to be valid for $xl~0.09.$ The experimental results are discussed in terms of the degenerate Coqblin-Schrieffer model with a crystalline electric field splitting \ensuremath{\Delta}\ensuremath{\simeq}330 K. The properties of the model, obtained by combining the lowest-order scaling and the perturbation theory, provide a satisfactory description of the experimental data down to 30 K. The experimental results between 20 K and 2 K are explained by the exact solution of the Kondo model for an effective doublet.

We present Hall-effect measurements on the heavy-fermion compound CePtSi. Above the temperature of antiferromagnetic ordering ${T}_{N}$, the Hall effect of CePtSi exhibits the behavior generally observed in heavy-fermion systems and ascribed to skew scattering. Below ${T}_{N}$ the Hall effect is enhanced and its field dependence is strongly nonlinear. We show that this behavior arises from skew scattering or anomalous velocity effects rather than from a change of the ordinary Hall effect induced by a reconstruction of the Fermi surface.