Novel Phases Exhibiting Tristable Switching

Abstract

The phase, designated as Sm CA *, which shows tristable switching was investigated in C8H17O–--COO–-COO*CH(CH3)C6H13 (MHPOBC) by means of thermal analyses, a miscibility test and microscope observation. The phase transition from Sm C* to Sm CA * is not observable by AC calorimetry but small peaks comparable to the Sm A-Sm C* transition are discernible in DSC. According to the miscibility test of racemic MHPOBC with a standard compound, this new phase was found to exist between Sm C* and Sm I* and not to be miscible with Sm Bhex. Therefore, the assignment of Sm CA * to one of the known phases is ruled out, which means that Sm CA * is a totally new phase. The difference between the pure enantiomer and the racemate is also pointed out.

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