The thermoelectric power (TEP), resistivity, and heat capacity of the polycrystalline Ce(Ni 1Àx Cu x ) 2 Al 3 system, for x ¼ 0.0-0.4, are reported. A clear enhancement of TEP at low temperatures is seen upon substitution of Cu and is expected to be useful for low-temperature thermoelectric applications. To understand such an enhanced TEP we have employed a twoband model based on the Ce-4f and conduction bands proposed by Gottwick et al. A clear evolution of a 4f band moving toward the Fermi level that is becoming sharpened is seen and is predicted to be close to resonance. The fit parameters of the TEP (S) are physically reasonable. The resistivity data shows an evolution from a simple compensated metal to a paramagnetic one via the Kondo route. This is in line with TEP parameters. In addition, a clear enhancement seen in the electronic part of the heat capacity upon Cu substitution and the evolution of magnetoresistance behavior corroborates the results. Possible bipolar effects are also taken into consideration along with an electron-phonon interaction term to explain the almost temperature-independent part of the resistivity, still yielding a considerable component of disorder.

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Heat capacity studies on the Kondo lattice system Ce(Ni 1−x Cu x ) 2 Al 3 , in the presence of magnetic fields, were reported for x = 0.0−0.4. The physical properties of the intermediate compositions like x = 0.3 and 0.4 were known for their enhanced thermoelectric power and hence have been analysed with an extra interest. It was alsoshown from the X-ray diffraction that these systems with x = 0.3 and 0.4 were in single phase in terms of sample purity and it stabilized the phases easily with the increase in the Cu doping in the system. The low temperature rise in C p /T below 10 K under the influence of high magnetic fields was analysed using a multi-level Schottky effect. A gradual decrease of the total angular momentum (J) with the increase of applied magnetic fields indicated a scenario of screening of Ce 3+ magnetic moment while simultaneously the system settled for the Fermi liquid state. The screening thus seen was in line with the expectations of electrical conductivity measurements on these samples.