密度泛函理论的电负性与氧化物超导性的关系

Study on the Correlation Between Elemental Electronegativity and Superconductivity of Oxides Utilizing Density Functional Theory

研究了稀土氧化物与元素电负性之间的关系。用电负性均衡值Xcq作为稀土氧化物超导电性新的判据依据，并用均方根公式确定稀土氧化物中元素电负性的均衡值Xcq集中在4．537—6．571，而电负性的均衡值在此范围之外的稀土氧化物都不具有超导性。

In this article, we have studied on electronegativity and superconductivity of rare-earth oxides, utilizing density functional theory, worked out the correlation between electronegativity and superconductivity for rare-earth oxides. It is sug- gested that the equalizing electronegativity（ Xcq ） of rare-earth can be used as an empirical criterion for superconductivity of rare-earth oxide. A new formula for the calculation of Xcq has been obtained. We have calculated the Xcq qvalues of supercon- ductivity of 200 rare-earth oxides, the result shows that the Xcq values concentrate in a narrow range of 4.537 to 6.571 and the elements with values outside this range the oxides will be non-superconductive, This criterion can be applied to almost all the rare-earth oxide superconductors. It is clearly that this article gives a new criterion for superconductivity of rare-earth oxide.