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Heavy fermion compounds represent one of the most strongly correlated forms of electronic matter and give rise to low temperature states that range from small moment ordering to exotic superconductivity, both of which are often in close proximity to quantum critical points. These strong electronic correlations are associated with the transfer of entropy from the local moment degrees of freedom to the conduction electrons, and, as such, are intimately related to the low temperature degeneracy of the (originally) moment bearing ion. Here we report the discovery of six closely related Yb-based heavy fermion compounds, Yb[T.sub.2][Zn.sub.20], that are members of the larger family of dilute rare earth bearing compounds: R[T.sub.2][Zn.sub.20] (T = Fe, Co, Ru, Rh, Os, Ir). This discovery doubles the total number of Yb-based heavy fermion materials. Given these compounds' dilute nature, systematic changes in T only weakly perturb the Yb site and allow for insight into the effects of degeneracy on the thermodynamic and transport properties of these model correlated electron systems. correlated electron | intermetallic compound

Research into single-crystalline UlrGe in magnetic fields up to 18 T applied along the principal axes is presented. Application of a magnetic field in UlrGe was found to convert the zero-field antiferromgnetic phase into a field-induced phase before entering the field-forced ferromagnetic phase.

It has been possible to obtain magnetization and specific-heat measurements of a CePtSn single crystal in magnetic fields up to 14 T applied along principal crystallographic axes. The low-temperature curves were found to show metamagnetic transitions that can be linked with previously observed GMR anomalies in magnetoresistance.

It has been possible to measure electrical resistance, magnetization and impedance spectroscopy in polycrystalline samples of La0.3Pr0.4Ca0.3MnO3 compounds. It is suggested that there is a phase separation below Tc in the compound in total alignment with recent muon spin relaxatoin and neutron spin echo measurements undertaken on manganites.

The single crystals of the antiferromagnetic compound U[Ni.sub.0.5][Sb.sub.2] ([T.sub.N] = 161 K) are studied by using measurements of magnetic susceptibility, specific heat and electrical resistivity at ambient pressure and resistivity under hydrostatic pressures. The effect of pressure is to raise [T.sub.N], while suppressing the amplitude of the small features in electrical resistivity versus temperature at lower temperatures and increasing the thermal hysteresis.

Muon spin relaxation measurements on U[Cu.sub.1.5][Sn.sub.2], which has crystallized in the Ca[Be.sub.2][Ge.sub.2]-type structure, are presented. Critical slowing down for the paramagnetic U spin fluctuations is not present, which is typical in first-order transitions, whereas the temperature dependence of the local field generated by the U spins is a second-order feature.