Small-angle X-ray scattering from micellar solutions of gemini surfactants

In an earlier work, we had studied small-angle neutron scattering (SANS) fr om micellar solutions of bis-cationic C16H33N+ (CH3)(2)-(CH2)(m)-N+ (CH3)(2 )C16H33, 2Br(-) gemini surfactants, referred to as 16-m-16. 2Br(-), for sev eral spacer lengths. This Le;ter reports the results of small-angle X-ray s cattering (SAXS) experiments on the above system for spacer lengths of m = 3, 4 and 12. It is seen that SAXS distributions are qualitatively different from the SANS distributions. These experiments show that a combined SANS a nd SAXS study can be used for obtaining information on the counterion distr ibution around the micelles, (C) 2000 Elsevier Science B.V. All rights rese rved.