Skutterudite化合物CoSb3的晶格結構中擁有一個空缺，我們利用核磁共振量測來了解當填充元素La至此空缺時，對於其費米能面之電子組態產生的影響。從中央譜線線寬可以看出La的填充濃度增加並沒有使LaxCo4Sb12感應出磁性，而測量奈特位移和自旋晶格鬆弛時間可以顯現出費米能階附近電子的分布組態。在低溫下測得的自旋晶格鬆弛速率可以發現所有的化合物都遵循著Korringa relation，主要歸因於在費米能階附近有限的載子數目；但在高溫中其載子卻有著和半導體相同的活性。整體的趨勢為半金屬特性。藉著剛體能帶模型我們可以清楚的來解釋核磁共振發現LaxCo4Sb12的費米能階態密度隨著填充濃度改變，與Seebeck coefficient得到的結果相符。

There have cages in the structure of the skutterudite compound CoSb3. In this study, we use nuclear magnetic resonance measurement to understand what effects of the electronic properties by filling La into those voids. The central line width doesn’t broaden that show us these are nonmagnetic compounds. Knight shift and spin lattice relaxation rate provide information about the electronic structure near the Fermi energy. NMR relaxation rate follow the Korringa relation in low-T because of the finite carriers at the Fermi level; in high-T, it has semiconductor-like activated form. All the distribution is semimetallic feature, we explain the observation of LaxCo4Sb12 Fermi level density of states change with a rigid-band model. The result is the same with Seebeck coefficient.

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