為了研究非理想配比（off-stoichiometry）效應對Heusler 金屬化合物Fe2-xTi1+xSn 的熱電性質的影響，我們在10K-400K 之間做了一系列的實驗。發現了幾個特點:
　　1.電阻率跟Seebeck 係數變化對非理想配比效應非常敏感。
　　2. Seebeck 係數的量測顯示出了我們已研究的這些樣品都是屬於p型的材料。其在室溫下有著大約20-30μV/K 的S 值。
　　3.Fe2TiSn 跟Fe2.05Ti0.95Sn 的Seebeck 係數之broad maximums 發生在330K 附近，此外，此最大值有隨著Ti 取代Fe 的比例慢慢增加，而右移至較高溫度之趨向。這些特色與能帶結構所推算出的結果相當一致。

　　We have studied the thermoelectric properties of the stoichiometric and off-stoichiometric Heusler compounds Fe2-xTi1+xSn between 10K and
400K.
　　It is found that the electrical resistivity and Seebeck coefficient are very sensitive to the off-stoichiometry.Seebeck coefficient measurements
indicate that all studied materials are p-type materials with moderate S values of about 20-30μV/K at room temperature.Broad maximums at
around 330K are observed in S for Fe2TiSn and Fe2.05Ti0.95Sn,and this maximum shifts to higher temperatures with replacing more Ti for Fe.These features are consistent with other experimental results and are related to issues raised by band structure calculations.

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