液态Hg－Na和Te－Se合金电输运性质及金属－非金属转变的研究

ELECTRICAL TRANSPORT OF LIQUID Hg-Na AND Te-Se ALLOYS AND METAL-NONMETAL TRANSITION

系统测量了液态Ｈｇ－Ｎａ及Ｔｅ－Ｓｅ合金的电阻率和热电势，发现液态Ｈｇ－Ｎａ合金的电阻率随成分变化虽有反常行为，但没有金属－非金属转变；而液态Ｔｅ－Ｓｅ合金的电阻率随成分变化并无反常出现，但当Ｓｅ成分大于３０％（ａｔ．）时，出现金属一非金属转变．本文考虑了液态Ｈｇ－Ｎａ合金中有Ｈｇ２Ｎａ瞬时短程序形成的因素，采用Ｆａｂｅｒ－Ｚｉｍａｎ理论，计算了液态Ｈｇ－Ｎａ合金的电阻率，计算结果与上述实验测量值符合很好．同时也定性解释了液态Ｈｇ－Ｎａ合金热电势极小值及液态Ｔｅ－Ｓｅ合金在大于３０％（ａｔ．）Ｓｅ时出现金属－非金属转变的原因．

The electrical resistivity and thermoelectric power of liquid Hg-Na and Ti-Se alloys have been measured. It is found that the composition dependence of resistivity of liquid Hg-Na alloy Shows anomalous behaviour and no metal-nonmetal transition. On the contrary,this dependence for liquld Te-Se alloy shows no anomalous behaviour but metalwnonmetal transition. Using Faber-Ziman theory and considering the formation of Hg,Na,the transient short rang ordered structure,In liquid Hg-Na alloy,the electrical resistivity is calculeted and it is in agreement very well with experiments. The minimum of the composition dependence of thermoelectric power for liquid Hg-Na alloy and the metal--nonmetal transition for liquid Te-Se alloy containing greater than 30at. % Se are explained qualitatively.