No abstract

Smectic liquid crystalline phases are formed due to the intermolecular hydrogen bonding in a binary mixture of phenol derivatives and 4,4′-bipyridine as the length of the terminal alkyl or alkoxyl chains are increased.

N-(4-Alkoxybenzylidene)-4-halogenoanilines have been synthesized, and the phase transitions determined using a differential scanning calorimeter and a polarizing microscope. Smectic and nematic phases have been observed for fluoro and chloro derivatives whereas bromo and iodo derivatives exhibit only a smectic phase.

Eight new homologous series of 4-alkyl-N -(4-alkloxysalicylidene)anilines were synthesized. The phase transitions of these homologues were determined using diOE erential scanning calorimetry and polarizing optical microscopy. The homologues began to exhibit liquid crystalline phases as the terminal alkyl or alkoxyl chains were lengthened. In addition, some members of these homologues series exhibited photochromism in the solid state.

The temperature dependence of specific heat for the compounds CeNi 4 Cu and YbNi 4 Cu is analysed. These studies are supported by magnetic susceptibility and x-ray photoemission spectroscopy measurements. The scheme of the energy levels created by the splitting due to the crystal electric field is determined from the Schottky contribution to the specific heat. Anomalies observed at low temperatures are discussed in the framework of heavyfermion/Kondo physics. It is found that an external magnetic field has a strong influence on the low temperature part of the specific heat.