Cholesteryl benzoate Subject

The blue phases occur in cholesteric systems of sufficiently low pitch, less than about 5000 A. They exist over a narrow temperature range, usually 1 C, between the cholesteric liquid crystal phase and the isotropic liquid phase (see (1.3.5)). The first observation of a blue phase was described by Reinitzer himself in his historic letter to Lehmann as follows On cooling (the liquid phase of cholesteryl benzoate) a violet and blue phenomenon appears, which then quickly disappears leaving the substance cloudy but still liquid. Although Lehmann recognized it as a stable phase, not until the 1970s was it generally accepted that the blue phases are thermodynamically distinct phases. The nature of these phases has now become a subject of considerable interest to condensed matter physicists. 

Phase transitions involving liquid crystalline phases have been the subject of experimental work for many years. By 1899 Hu-lett [1] had already investigated 4,4 -bis-methoxy-azoxybenzene, 4,4 -bi s-ethoxy-azoxybenzene and cholesteryl benzoate up to 30 MPa. After a long period of inactivity... 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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