Title:	Effect of skew cybotactic structure on the optical properties of a nematogen with a lateral cyano substituent
Authors:	Madhusudana, N.V. Moodithaya, K.P.L. Suresh, K.A.
Issue Date:	Oct-1983
Publisher:	Gordon and Breach Science Publishers.
Citation:	Molecular Crystals and Liquid Crystals, 1983, Vol.99, p239-247
Abstract:	We report an unusual thermal variation of the ordinary refractive index (no) of the nematogenic compound 2-cyano-4-heptyl-phenyl-4'-pentyl-4-biphenyl carboxylate, which has a cyano group making a large angle (~60°) with the molecular axis. As the sample is cooled from the NI transition point, no initially decreases as usual, but on further cooling it shows an increasing trend after reaching a broad minimum. On the other hand, the extraordinary index ne shows the normal temperature variation. X-ray investigations of a monodomain sample show that the nematic has a skewed cybotactic type of short-range order, the tilt angle increasing considerably as the temperature is lowered from the NI transition point. We have made a model calculation to explain the temperature variation of no in terms of the variation of the tilt angle.
Description:	Restricted Access. Paper presented at the 9th international conference on liquid crystals held at Bangalore in 1982.
URI:	http://hdl.handle.net/2289/2496
ISSN:	1058-725X
Alternative Location:	http://dx.doi.org/10.1080/00268948308072045
Copyright:	1983 OPA (Overseas Publishers Association) N.V.
Appears in Collections:	Research Papers (SCM)

Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.