Abstract
Abstract Optical birefringence and dichroism have been studied in physical steroid organogels. We have used two complementary derivatives (SNH and SNO*) in cyclohexane: the former has no chromophoric group in the 220–800 nm wavelength range studied, in contrast with the latter. The dichroism is mainly due to linear contributions. The amplitude of the signal is correlated with the growth of fibrillar structures and specially with the heterogeneities of the gel network which was assumed to be chiral fibrillar junction zones. The characteristic SNO* dichroic absorptions (for C ≈ 2.0 × 10−2 M) are λmax = 250nm, |Δϵ| ≈ 6.0 (mainly a linear contribution) and λmax = 450 nm, Δϵ = +0.45 (mainly a circular contribution). These preliminary observations provide strong evidence for a helical stacking of the steroid molecules within the fibres of the gel samples. The optical dichroic absorption can be a valuable technique to monitor the orientational order of the microdomains crossed by the light beam.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
