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Low-energy excitations in electron-doped metal phthalocyanine from NMR in Li$_{0.5}$MnPc

M. Filibian·P. Carretta·T. Miyake·Y. Taguchi·Y. Iwasa
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Abstract

$^7$Li and $^1$H NMR and magnetization measurements in \lpc (Pc$\equiv$C$_{32}$H$_{16}$N$_8$), recently proposed as a strongly correlated metal, are presented. Two different low-frequency dynamics are evidenced. The first one, probed by $^1$H nuclei gives rise to a slowly relaxing magnetization at low temperature and is associated with the freezing of MnPc $S=3/2$ spins. This dynamic is similar to the one observed in pristine $β$-MnPc and originates from Li depleted chain segments. The second one, evidenced by $^7$Li spin-lattice relaxation rate, is associated with the hopping of the electrons along Li-rich chains. The characteristic correlation times for the two dynamics are derived and the role of disorder is briefly discussed.

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M. Filibian, P. Carretta, T. Miyake, Y. Taguchi, Y. Iwasa. 2006-07-26. Low-energy excitations in electron-doped metal phthalocyanine from NMR in Li$_{0.5}$MnPc. https://doi.org/10.1103/physrevb.75.085107

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