Spin-Lattice Relaxation of Dipolar Energy in Fluid Confined to Nanosize Cavities

Abstract

We shown that by means of the two pulse sequence, the spin system of a liquid entrapped into nanosize cavities can be prepared in quasi-equilibrium states of high dipolar order. Then the dipolar order relaxes to thermal equilibrium with the lattice with a relaxation time T1d. It was shown that large number of spins T1d increases as the square to the concentration of the molecules C and decreases as inverse of the number of spins, T1d - C²/N. Study of spin lattice relaxation of dipolar energy in a spin system under the bounded region is important for extracting very useful parameter characterized nanomaterials from NMR experimental data.