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arXiv · 0808.2621

Magnetization and spin dynamics of a Cr-based magnetic cluster: Cr$_{7}$Ni

A. Bianchi·S. Carretta·P. Santini·G. Amoretti·Y. Furukawa·K. Kiuchi·Y. Ajiro·Y. Narumi·K. Kindo·J. Lago·E. Micotti·P. Arosio·A. Lascialfari·F. Borsa·G. Timco·R. E. P. Winpenny
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Abstract

We study the magnetization and the spin dynamics of the Cr$_7$Ni ring-shaped magnetic cluster. Measurements of the magnetization at high pulsed fields and low temperature are compared to calculations and show that the spin Hamiltonian approach provides a good description of Cr$_7$Ni magnetic molecule. In addition, the phonon-induced relaxation dynamics of molecular observables has been investigated. By assuming the spin-phonon coupling to take place through the modulation of the local crystal fields, it is possible to evaluate the decay of fluctuations of two generic molecular observables. The nuclear spin-lattice relaxation rate $1/T_1$ directly probes such fluctuations, and allows to determine the magnetoelastic coupling strength.

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A. Bianchi, S. Carretta, P. Santini, G. Amoretti, Y. Furukawa, K. Kiuchi, Y. Ajiro, Y. Narumi, K. Kindo, J. Lago, E. Micotti, P. Arosio, A. Lascialfari, F. Borsa, G. Timco, R. E. P. Winpenny. 2008-08-19. Magnetization and spin dynamics of a Cr-based magnetic cluster: Cr$_{7}$Ni. https://arxiv.org/abs/0808.2621

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