钙钛矿结构材料SrHfO_3的电子结构研究

Electronic Structure of Perovskite SrHfO_3

在密度泛函理论框架下首先用局域自旋密度近似(LSDA)方法,研究了具有钙钛矿结构的材料SrHfO3的电子结构,发现Sr显示比较明显的离子特性,Hf和O之间由于杂化形成了共价键。得到该化合物的带隙为1.54eV,磁矩为零。考虑Hf5d局域电子之间的在位库仑相互作用(即采用LSDA+U方法进行计算)后,磁矩依然为零,但态密度分布有明显的改变。计算结果表明,该材料中Hf5d之间的在位库仑相互作用U为8.0eV。

In this article, the electronic structure of perovskite SrHfO3 has been studied by local （spin-） density approximation （LSDA） within the framework of density functional theory （DFT） firstly. Strontium has been found to show an obvious ionic character and the interaction between Hf and O found to be weakly covalent. The gap of the compound acquired is 1.54 eV and the magnetic moment is still found to be zero. After the on-site Coulomb interaction U has been calculated, the magnetic moment remains zero, but the distribution of the density shows an obvious change. Tile calculations showed that the Coulomb interaction between Hf and 5d is 8.0 eV.