Two new mesophases in a chiral compound
نویسندگان
چکیده
2014 Microscopical, miscibility and X-ray studies establish the existence of two new mesophases in the two enantiomers of 1 (methyl)-heptyl terephthalidene bis amino cinnamate. In one of this two mesophases the two enantiomers do not exhibit a total miscibility range; while for the second the untwisted form observed with the racemic mixture has a higher temperature range of stability than the twisted form observed for the pure enantiomers. Information about the structures of the two phases is given and a comparison is made with the S*C and SD phases. Nevertheless the location of these two phases in the sequence of the presently known calamitic mesophases is not yet completely established. J. Physique 44 (1983) 623-629 MAI 1983,
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