Is there a reference explains in details how to determine the liquid crystal phase? how to know the sample is nematic, smectic or cholesteric experimentally?
Google is your friend: http://bfy.tw/D2aZ
As a start I'd recommend the book by George Gray (Molecular structure and the properties of liquid crystals Gray, G. W., Academic Press, London New York (1962)
Second: Liquid Crystals (Cambridge Monographs on Physics) Chandrasekhar, S.,Cambridge University Press (1977)
I saw this review little time ago http://www.ipme.ru/e-journals/RAMS/no_44416/06_44416_an.pdf
You need it for a lab? For yourself? What equipment do you have available? The easiest way would be with polarized optical microscopy.
Nematic and cholesterics can be easily seen with thir textures. Low order smectics too. For high order you would need XRD, hopefully 2D detector/film on an aligned sample.
There's also a lot of info/references on the LC handbook:
http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527327738.html
Dear Shaban
This is a very interesting field. For understand this physical as well as the chemical behavior of this kind of materials, you have synthesized that material or it is also available in the market. With the help of polarizing microscope (it is easily available)......you may be got some idea regarding the shape of the crystal.............matching all that with standard pictures that were earlier published......
Try also Peter J Collings Liquid crystals: nature's delicate phase of matter Princeton University Press (1990) and the classic:
The Microscopy of Liquid Crystals (Monographs in Microscope Series 48)
Norman H. Hartshorne, Microscope Pubns Ltd (1974)
As stated above you need a microscope preferably with a hot stage and polarizers to observe and categorize the phases.
From carefuly observation from POM, at room temperature you show different texture pattern of solid crystal all the molecules are highly bind to easy other by different forces but when you increase the temperature, gaining of entropy and enthalpy the textural pattern transform into nice texture pattern and it is totally different from solid crystal and the mobility of LCs is higher and also be stable and continue to apply further heating it transform into isotropic state (Liquid state). Take standard reported samples like 5-CB, or 4-n-alkoxy benzoic acids or any cholesteric benzoates etc............
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