Study for Electron Affinitive and emissive characteristics of Various Impurities in Silicone Oil.

该项目是为了研究硅油中各种杂质的电子亲和和电子发射特性，即哪些杂质容易成为负离子或正离子。用薄膜隧道发射体将电子和空穴注入到两种硅油中，一种是用分馏柱蒸馏得到的，另一种是被杂质污染的，根据注入电子和空穴的能级，计算了硅油中各种杂质的电子亲和能力和电子发射能力。得到了不同杂质的电子亲和力为0~0.6 eV，电子发射能量为2~3 eV。实验结果表明，电子亲和和电子发射特性强烈地依赖于杂质的结构。很明显，具有如下特殊结构的杂质具有很强的电子亲和力。(1)由氧和铬等强酸性原子组成的杂质。(2)电荷局域并具有较大偶极矩的杂质。(3)具有双键电子的大分子杂质，具有相当容易移动的电子。当施加电场时，结构(2)和(3)的杂质似乎具有降低碱与硅油界面电子发射的势垒高度的效果，从而使偶极的局域场。换句话说，这样的杂质应该有很大的电子亲和力。另一方面，很明显，结构(2)和(3)的杂质也有相当大的电子发射能力。此外，具有借出电子对的杂质具有电子发射的能力。

The project was performed to investigate electron affinitive and electron emissive characters of various impurities in silicone oil, namely which kinds of impurities became easily negative or positive ions. Electron and hole were injected by a thin film tunnel emitter into two kinds of silicone oils, i.e. one was distilled by a fractionating column and another was contaminated by a dose of impurity.From the injection levels of electron and hole into such silicone oils, electron affinitive and electron emissive ability of various impurities in silicone oil were calculated. The values from 0 to 0.6 eV of electron affinity and values from 2 to 3 eV of energy for electron emission were acquired for various impurities.From the experimental results, it was found that the electron affinitive and electron emissive characters depended strongly on the structure of impurities. It became clear that such impurities having special structures as the followings had strong electron affinity.(1) Impurities made of strongly acid atoms like oxygen and chroline. (2) Impurities in which charge was localized and having large dipole moment. (3) Impurities of a large molecule with double bonds having <pi> electron which was able to move considerably easily.When electrical field is applied, the impurities of the structures (2) and (3) seem to give an effect of lowering the barrier hight for electron emission at the interface between a base and silicone oil for the sake of local field by the dipole. In other words such impurities should have large electron affinity.On the other hand it became clear that the impurities of structure (2) and (3) had a considerably large ability for electron emission also. Furthermore impurities which had loan electron pairs had an ability for electron emission.