NEUTRON-SCATTERING INVESTIGATION OF A MACROSCOPIC SINGLE-CRYSTAL OF ALYOTROPIC L-ALPHA PHASE

Water-rich lamellar samples of the quaternary microemulsion SDS-pentan ol-water-dodecane have been prepared in form of 1 mm x 10 mm x 20 mm m acroscopic mono-domains. The shape is given by the quarts cuvette cont aining the sample, the layer planes are parallel to the cuvette walls. Diffraction patterns and ''rocking curves'' have been obtained by neu tron diffraction using a triple-axis spectrometer. Three ''pseudo-Brag g peaks'' have been observed, their (relative) intensities yield a new experimental access to estimate the product of the elastic constants eta(-2) proportional to B kappa resulting in a lower value than obtain ed from synchrotron investigation using peak shape fitting (Roux D. et al., Micelles, Membranes, Microemulsions and Monolayers (Springer, Ne w York, Berlin) 1994).