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arXiv · 1011.1141

Low-energy spin dynamics in the [YPc2]0 S=1/2 antiferromagnetic chain

F. Branzoli·P. Carretta·M. Filibian·S. Klyatskaya·M. Ruben
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Abstract

1H nuclear magnetic resonance (NMR) measurements in [YPc2]0, an organic compound formed by radicals stacking along chains, are presented. The temperature dependence of the macroscopic susceptibility, of the NMR shift and of the spin-lattice relaxation rate 1/T1 indicate that the unpaired electron spins are not delocalized but rather form a S=1/2 antiferromagnetic chain. The exchange couplings estimated from those measurements are all in quantitative agreement. The low-energy spin dynamics can be described in terms of diffusive processes and the temperature dependence of the corresponding diffusion constant suggests that a spin-gap around 1 K might be present in this compound.

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F. Branzoli, P. Carretta, M. Filibian, S. Klyatskaya, M. Ruben. 2010-11-04. Low-energy spin dynamics in the [YPc2]0 S=1/2 antiferromagnetic chain. https://doi.org/10.1103/physrevb.83.174419

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