Freeze-fracture electron microscope observations of the blue phase III.

TEM of CE4 (chiral 4-(2-methylpentylphenyl)- 4'-hexyloxybenzoate) quenched from its cholesteric and blue phases (BP) I and III are presented. Images of cholesteric and BP I are consistent with an earlier study of similar compounds. CE4 quenched from its BP III is a spaghetti-like tangle of filamentary objects of 10 to 50 nm diameter and lengths of 0.1 to 1 micron. These are likely double-twist cylinders in a liquid-like arrangement, melted from their lattice structure in the BP I and II. BP III apparently has a basic, double-twisted structure whose sense and length scale correspond to BP I and BP II, but without the latter's long-range periodicity.