Isotope substitution effects on spin dynamics of the molecular nanomagnet Fe8 cluster studied by NMR

摘要

We have carried out H-1 NMR at T = 1.5 K in both Fe-57-enriched Fe8 cluster and non-enriched Fe8 cluster to investigate isotope substitution effects on magnetic properties. The field dependence of 1/T-1 can be fitted well by using a simple model in terms of the thermal fluctuations of the total spin S = 10 of the cluster originating from the spin-phonon interactions. The absence of a difference of the magnetic field dependence of 1/T-1 between the two systems indicates that the spin-phonon coupling constant is not affected by the change of mass of the isotopes in the Fe8 cluster. (C) 2003 Elsevier Science Ltd. All rights reserved. [References: 8]