| Autor: |
Morton, John J. L., Tyryshkin, Alexei M., Ardavan, Arzhang, Porfyrakis, Kyriakos, Lyon, S. A., Andrew D. Briggs, G. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 1/7/2006, Vol. 124 Issue 1, p014508, 5p, 6 Graphs |
| Abstrakt: |
We examine the temperature dependence of the electron spin relaxation times of the molecules N@C60 and N@C70 (which comprise atomic nitrogen trapped within a carbon cage) in liquid CS2 solution. The results are inconsistent with the fluctuating zero-field splitting (ZFS) mechanism, which is commonly invoked to explain electron spin relaxation for S>=1 spins in liquid solution, and is the mechanism postulated in the literature for these systems. Instead, we find an Arrhenius temperature dependence for N@C60, indicating the spin relaxation is driven primarily by an Orbach process. For the asymmetric N@C70 molecule, which has a permanent ZFS, we resolve an additional relaxation mechanism caused by the rapid reorientation of its ZFS. We also report the longest coherence time (T2) ever observed for a molecular electron spin, being 0.25 ms at 170 K. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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