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The envelopes of spin-echo amplitudes obtained with trains of multiple refocusing pulses are normally modulated by homonuclear scalar couplings. Echo modulations make it difficult to determine transverse relaxation rate constants R2. Provided that the puls ...
In systems with dipolar relaxation in isotropic phase, it is possible to measure the extent of cross correlation of the fluctuations of two selected dipole-dipole interactions A-M and A-X by selectively exciting and spin-locking the transverse magnetizatio ...
By analogy to heteronuclear systems, coherence can be transferred adiabatically in the rotating frame between two selected spins I and S belonging to a homonuclear network of scalar-coupled spins. In contrast to cross polarization with const. radiofrequenc ...
C59N magnetic fullerenes were formed inside single-wall carbon nanotubes by vacuum annealing functionalized C59N molecules encapsulated inside the tubes. A hindered, anisotropic rotation of C59N was deduced from the temperature dependence of the electron s ...
We investigate the spin relaxation of negatively charged excitons in modulation-doped CdTe quantum wells by time-resolved photoluminescence. The charged exciton spin flip process is found to be very sensitive to the excitation energy but not to a change of ...
The enhancement of the spin-lattice relaxation rate for nuclear spins in a ligand bound to a paramagnetic metal ion [known as the paramagnetic relaxation enhancement (PRE)] arises primarily through the dipole-dipole (DD) interaction between the nuclear spi ...
We have used electrically detected magnetic resonance (EDMR) to study the spin dependent processes on the operation of diodes based on poly(2-metoxy-5-(2'-etil-hexiloxy)-1,4-phenylene vinylene) (MEH-PPV) and on tris-8-hydroxyquinoline-aluminum (Alq3
A detailed analysis of nitrogen-15 longitudinal relaxation times in microcrystalline proteins is presented. A theoretical model to quantitatively interpret relaxation times is developed in terms of motional amplitude and characteristic time scale. Differen ...
New exptl. methods are presented that allow one to measure cross-correlation between the fluctuations of dipolar interactions and chem. shift anisotropy (CSA) in scalar coupled systems with two and three spins I = 1/2 in isotropic soln. The methods involve ...
In crowded NMR spectra, it is shown how longitudinal relaxation rates (lab.-frame rates 1/T1) can be measured by selective inversion-recovery of a chosen site A followed by selective transfer of magnetization to another site X through a scalar coupling JAX ...