International Workshop on Geometry and Interfaces

J. Phys. Colloques 51 (1990) C7-375-C7-381
DOI: 10.1051/jphyscol:1990737

STRUCTURAL FEATURES OF THE CUBIC PHASE OF A TERNARY SURFACTANT SYSTEM

S. RADIMAN¹, C. TOPRAKCIOGLU^{1, 2}, L. DAI¹, A.R. FARUQI³, R.P. HJELM Jr.⁴ and A. de VALLERA<sup>5

1</sup>  Cavendish Laboratory, Madingley Road, GB-Cambridge CB3 OHE, Great-Britain
²  AFRC Institute of Food Research, Colney Lane, GB-Norwich NR4 7UA, Great-Britain
³  MRC Laboratory of Molecular Biology, Hills Road, GB-Cambridge CB2 2QH, Great-Britain
⁴  LANSCE, Los Alamos National Laboratory, Los Alamos NM 87545, U.S.A.
⁵  Department of Physics, University of Lisbon, P-1700 Lisbon, Portugal

Abstract
We have studied the cubic phase formed by the ternary system water/didodecyldimethylammonium bromide/octane using small-angle x-ray and neutron scattering. We have observed the existence of more than one symmetry in this cubic region, with a transition from primitive to body centred cubic symmetry on increasing the water content of the system. Our results are consistent with a bicontinuous periodic structure of constant mean curvature. We also report rheological measurements which indicate that the ringing behaviour of the cubic samples is associated with a sharp increase in the quality factor as audible frequencies are approached.

© EDP Sciences 1990