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The results of elastic, quasielastic, and inelastic neutron-scattering studies on polycrystalline CeM 2 Ge 2 (M=Ag, Au, and Ru) are presented. All compounds reveal long-range magnetic order at low temperatures. Ferromagnetic (M=Ru), antiferromagnetic (M=Au), and incommensurate (M=Ag) structures were detected. Using time-of-flight (TOF) techniques, the crystalline electric-field splittings were determined. With high-resolution TOF experiments the temperature and wave-vector dependence of the magnetic relaxation rate was studied

X-ray diffraction and dielectric measurements have been performed on the molecular crystal CsCN as a function of temperature. The order parameter of the cubic to rhombohedral phase transition (Tc=186 K) was determined and interpreted by a coupling of the (CN)− orientations to the shear strain. At lower temperatures the dielectric response is dominated by thermally activated relaxations processes rather than by electrical ordering of the CN dipoles.

The crystal field splittings of the 4f-states in Er(Tl 1- c Pb c ) 3 and Pr(Tl 1- c Pb c ) 3 (cubic, Cu 3 Au-structure) have been investigated by inelastic neutron scattering. The crystal fields are cubic for all mixing ratios c . The crystal field parameters vary linearly with c . The results demonstrate the failure of the point charge model and emphasize the role played by the ligands.

Specific heat, resistivity and inelastic neutron scattering experiments are reported, which demonstrate that CeNi 2 Ge 2 exhibits a heavy-fermion groundstate which is neither magnetic nor superconducting. The specific heat coefficient γ( T ) reaches 350 mJ/K 2 mol and exhibits a peak at 0.4 K showing that coherence effects become important at low temperatures. The magnetic relaxation rates as measured via the line width in inelastic neutron scattering experiments are strongly enhanced and deviate from a Korringa law behaviour. The Kondo temperature T K ≈ 30 K was determined from the magnetic relaxation rates and from the specific heat data.