Nuclear spin-lattice relaxation of dipolar order caused by paramagnetic impurities Academic Article uri icon

abstract

  • We show that the relaxation function of the dipolar order is given by exp@2(t/T1d a )#exp(2t/T1d b ) where T1d a and T1d b are spin-lattice relaxation times: T1d a due to direct interaction of a given nuclear spin with paramagnetic centers and T1d b due to indirect interaction with the paramagnetic centers through neighboring nuclear spins. For a homogeneous distribution of paramagnetic centers and nuclear spins, a5D/6 where D is the sample dimensionality. For an inhomogeneous distribution, the sample is divided into d-dimensional subsystems, each containing one paramagnetic center, yielding a5(D1d)/6. The dipolar relaxation is measured in fluorinated graphite. Data from this experiment and from CaF2 doped with Mn 21 in the literature are consistent with this model. @S0163-1829~97!04501-3#

publication date

  • January 1, 1997