Spin relaxation


Environmental effects on electron spin relaxation in N@C60 

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We have studied the environmental effects of surrounding nuclear spins on the electron spin relaxation of the N@C60 molecule (which consists of a nitrogen atom at the center of a fullerene cage). Using dilute solutions of N@C60 in regular and deuterated toluene, we observe and model the effect of translational diffusion of nuclear spins of the solvent molecules on the N@C60 electron spin relaxation times. We also study spin relaxation in frozen solutions of N@C60 in CS2, to which small quantities of a glassing agent, S2Cl2, are added. At low temperatures, spin relaxation is caused by spectral diffusion of surrounding nuclear 35,37Cl spins in the S2Cl2, but, nevertheless, at 20 K, T2 as long as 0.23 ms is observed.

Environmental effects on electron spin relaxation in N@C60

John J. L. Morton, Alexei M. Tyryshkin, Arzhang Ardavan, Kyriakos Porfyrakis, S. A. Lyon and G. Andrew D. Briggs
Physical Review B 76 085418 (2007) Link


The effects of a pyrrolidine functional group on N@C60 

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Relaxation in unmodified N@C60 has been found to depend on vibrational modes of the N@C60 molecule itself, however if the fullerene is modified by a functional group in such a way as to introduce a zero-field-splitting (ZFS), the fluctuation of this ZFS due to molecular tumbling in liquid solution provides an additional relaxation pathway. Using pulsed EPR we observed this additional relaxation and use it to obtain estimates of the magntidue of the ZFS, and the molecular tumbling correlation time.

The effects of a pyrrolidine functional group on the magnetic properties of N@C60

Jinying Zhang, John J. L. Morton, Mark R. Sambrook, Kyriakos Porfyrakis, Arzhang Ardavan and G. Andrew D. Briggs
Chemical Physics Letters 432 523 (2006) Link


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