Proton spin relaxation in a smectic liquid crystal

✍ Scribed by Ronald Y. Dong; M. Wiszniewska; E. Tomchuk; E. Bock

• Publisher: Elsevier Science
• Year: 1974
• Tongue: English
• Weight: 327 KB
• Volume: 25
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(74)89143-8

✦ Synopsis

A proton spin relaxation study in the liquid crystal ethyl-~(metho~ybanzyI~dene~-amino] cinnsmate is presented,

A "phase change" is observed at a 103'C within the smectic A phase. Some iiquid-like mobility exists below this temperature.

Recent studies in liquid crystals [I] by means of proton spin relaxation [2] have focused mainly on the nematic type. In the nematid mesophase, there exists a Iong range orientational order among rod-fike rnolecules in an external magnetic field_ The smectic phase consists of layers. Within each layer, the preferred direction of thelong axis of each molecule (director) may be parallel to the planar normal (smectic A), or tilted with respect to the planes of the layers (smectic C). In both these phases no.long range positional order exists within the pIanes_ There exists a long range positional order within the planes in a smectic B phase.