Nuclear Magnetic Relaxation in Micellar Systems. Influence of Micellar Size

Article abstract of DOI:10.1021/j100285a027

An extensive 2H NMR relaxation study for hexadecyltrimethylammonium chloride micelles, with spin-lattice relaxation rates measured at nine magnetic field strengths and spin-spin relaxation rates at three magnetic fields strenghts, is presented.The measured relaxation rates show a strong dependence upon the magnetic field strength, and the data are anlyzed with the "two-step" model of ralaxation.A comparison is made with previously reported relaxation data for dodecyltrimethylammonium chloride micelles and the two-step model proves to be an excellent description of NMR relaxation in spherical micellar systems.Moreover, the motion causing the frequency dependence in the NMR relaxation can be described with an exponential correlation function with a correlation time that increases with the size of the spherical micelles.