摘要：
本研究是以不同方法下去分析當Mo漸漸加入到 中形成 時，Mo和Fe價數是否也會有所變化。在ESCA分析中發現還原氣氛燒結下試片，當加入的Mo含量超過x=0.6時，Mo的價數會由5價居多的狀況轉變成6價居多的狀況。同樣的試驗在空氣下燒結的試片並沒有發生，都是以Mo 6價顯現。Mo 6價比5價的離子半徑來的更小，所以低Mo含量時以5價居多的結果，證實在還原氣氛下燒結所產生的氧空缺，可以有效的促進Mo擴散進入 。當Mo含量達到一個門檻時，Mo才改以6價的狀態繼續的進入 中。
在熱分析實驗中證實在Mo含量高的試片中，仍然有氧空缺的存在，不過比起低Mo含量的試片來的低很多。而電性量測的實驗也可以直接證實在Mo含量未高過x=1.0時，Tc溫度下的電子傳導機制以跳躍為主，並且也符合Mo含量增加可以降低電阻率的預測。

Abstract
In this study , we observed the valence of Mo and Fe when different ratio of Mo added to to perform .In the ESCA analysis for samples sintering in reducing atmosphere , we found that the valence of Mo changed from 5 to 6 when the ratio of Mo exceeded more than x=0.6. When the same test for samples sinter in air, the result was different and all the valences of Mo were 6. Because the ionic radius of Mo with valences in 6 was smaller than 5 , it could prove that the oxygen vacancy obtained from sintering in reducing atmosphere can enhance the Mo ion to diffuse into with the Mo valences in 5 when samples contained low ratio of Mo. This phenomenon occurred until the ratio of Mo reached too high , and the Mo started to diffuse into with valences in 6.
In the thermal analysis , we could find the existing of oxygen vacancy in the samples with high ratio of Mo. But its quantity was much less than the sample with low ratio of Mo. In electrical measurement, we also found that the conduction mechanism of electrons and the hopping theory fitted well with the prediction of the quantity of Mo in previous literature when the ratio of Mo was not more than x=1.0 and the temperature was lower than Tc.

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