We present muon spin relaxation and 1H NMR results on the magnetically frustrated keplerate molecule Mo72Fe30, aimed at studying the local spin dynamics as a function of temperature. We find that, in common with other molecular magnets, the relaxation spectrum of this material is characterized by a single dominating electronic correlation time t. Experiments and theory show that t has a thermally activated behavior with an activation gap of the order of the energy difference between the lowest-lying rotational bands in this material. This shows that, in the intermediate temperature range just above 1 K, the relaxation of the electronic spin system occurs via Orbach processes involving energy levels belonging to the two lowest-lying rotational bands. Our data thus provide an experimental estimate of the first interband gap.
Scheda prodotto non validato
Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo
Titolo: | Low-energy spin dynamics in the giant keplerate molecule Mo72Fe30: A muon spin relaxation and 1H NMR investigation |
Autori: | |
Data di pubblicazione: | 2007 |
Rivista: | |
Abstract: | We present muon spin relaxation and 1H NMR results on the magnetically frustrated keplerate molecule Mo72Fe30, aimed at studying the local spin dynamics as a function of temperature. We find that, in common with other molecular magnets, the relaxation spectrum of this material is characterized by a single dominating electronic correlation time t. Experiments and theory show that t has a thermally activated behavior with an activation gap of the order of the energy difference between the lowest-lying rotational bands in this material. This shows that, in the intermediate temperature range just above 1 K, the relaxation of the electronic spin system occurs via Orbach processes involving energy levels belonging to the two lowest-lying rotational bands. Our data thus provide an experimental estimate of the first interband gap. |
Handle: | http://hdl.handle.net/11571/105187 |
Appare nelle tipologie: | 1.1 Articolo in rivista |