BONETTO fernando Jose
capítulos de libros
Acoustically Stimulated NMR Relaxometry. Application to the Study of Molecular Dynamics in Liquid Crystalline Materials
Modern Magnetic Resonance
Lugar: Berlin; Año: 2006; p. 1 - 6
The study of NMR relaxation with simultaneous sonication provides a new tool for the investigation of collective dynamics in mesomorphic systems. A topic of high interest is, for instance, how a sonic field can be used to influence an ordered molecular arrangement thus changing the rheological properties of the assembly. Within this picture, NMR relaxometry can be used to monitor sound-induced dynamical features that take place at microscopic level, as a means of achieving a comprehensive description of the involved processes. The main advantage of this newly proposed method relays in the possibility of disentangling between different mechanisms that cannot be identified in a simple T_1 dispersion experiment. From a technical standpoint, the evolution of this acoustically stimulated relaxometry technique encourages further instrumental development. A challenging task is, for instance, the design of special combined NMR and sonication probes, allowing to scan the acoustic frequency while keeping a precise control of the involved acoustic parameters. On a different way, the study of other NMR relaxation parameters like T_{1D} or T{1 ho} under sonication looks appealing for many reasons. Firstly, it may allow to display the involved information in terms of a different spectral density set. Secondly, with a careful experimental management, individual and collective contributions may be selectively filtered out. A deeper discussion on this topic is left for future work as being matter of current active development.