Conformation of an Alkane Chain in Confined Geometry: Cetyl Trimethyl Ammonium Ion Intercalated in Layered $CdPS_3$

Venkataraman, NV and Vasudevan, S (2000) Conformation of an Alkane Chain in Confined Geometry: Cetyl Trimethyl Ammonium Ion Intercalated in Layered $CdPS_3$. In: Journal of Physical Chemistry B, 104 (47). pp. 11179-11185.

PDF jp001654x.pdf - Published Version Restricted to Registered users only Download (199kB) | Request a copy

Abstract

Cetyl trimethylammonium (CTA) ions have been confined at low grafting densities within the galleries of layered $CdPS_{3}$ by an ion-exchange intercalation reaction to give $Cd0._{9^3}PS_{3}$$(CTA)_{0.^14}$. Intercalation occurs with a lattice expansion of 4.8 Å with the methylene “tail” of the intercalated surfactant lying closer to the walls of the galleries, rather than in the center. ${^13}$ C NMR and orientation-dependent IR vibrational spectroscopy of single crystals of the intercalated $Cd0._{9^3}$$PS_{3}$$(CTA)_{0.^14}$ have been used to probe the conformation and orientatio of the methylene tail of the isolated, interlamellar surfactant ions. We find that the confined methylene chain adopts an essentially all-trans conformation, even in the absence of intermolecular interactions, with a large section of the molecular plane of the trans chain aligned parallel to the walls of the galleries. Upon lowering of the temperature, increasingly larger sections of the molecular plane align parallel, so that the methylene chain lies flat, rigid, and aligned to the confining surface.

Item Type:	Journal Article
Publication:	Journal of Physical Chemistry B
Publisher:	American Chemical Society
Additional Information:	Copyright of this article belongs to American Chemical Society.
Department/Centre:	Division of Chemical Sciences > Inorganic & Physical Chemistry
Date Deposited:	24 Dec 2008 05:26
Last Modified:	29 Sep 2010 07:16
URI:	http://eprints.iisc.ac.in/id/eprint/16725

Actions (login required)

View Item