NMR and EPR studies of the organic conductor [dimethyl(ethylenedithio)diselenadithiafulvalene ] 2 Au(CN) 2 <mml:mrow…
1988; American Physical Society; Volume: 38; Issue: 1 Linguagem: Inglês
10.1103/physrevb.38.39
ISSN1095-3795
AutoresKazushi Kanoda, Toshihiro Takahashi, Toru Tokiwa, Kôichi Kikuchi, Kazuya Saito, Isao Ikemoto, Keiji Kobayashi,
Tópico(s)Perovskite Materials and Applications
ResumoThe low-temperature electronic state of an organic conductor [dimethyl(ethylenedithio) diselenadithiafulvalene${]}_{2}$Au(CN${)}_{2}$ [(DMET${)}_{2}$Au(CN${)}_{2}$] has been investigated by means of EPR and $^{1}\mathrm{NMR}$ measurements. The electron-spin susceptibility determined by EPR signal intensity shows temperature-insensitive Pauli paramagnetism at high temperatures, and decreases abruptly below 25 K, indicating a metal-insulator transition. The NMR linewidth exhibits a remarkable broadening below 20 K, and an enhancement of the nuclear-spin--lattice relaxation rate ${T}_{1}^{\mathrm{\ensuremath{-}}1}$ was observed around 15--20 K. These NMR data unambiguously indicate that the insulating phase is a magnetic state, very probably a spin-density-wave state. The absence of EPR line broadening at the transition is discussed.
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