Relativistic current- and spin-density functional theory and its application to f-electron systems

相对论电流和自旋密度泛函理论及其在 f 电子系统中的应用

基本信息

批准号：
09640424
负责人：
HASEGAWA Akira
金额：
$ 1.86万
依托单位：
NIIGATA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640424/
关键词：
Heavy electron systems Hund's rules Uranium compounds Electronic structure Fermi surface Relativistic current- and spin-density functional theory Spin-orbit interaction Orbital current 一般化密度勾配近似相対論的バンド理論一電子方程式電流及びスピン密度汎関数法 f電子系

项目摘要

In order to calculate the electronic structure for f-electron compounds, in which the f electrons are itinerant and responsible to magnetism, it is necessary to take into account the magnetic effects that originate from the spin polarization and the orbital current besides relativistic effects. For a system of interacting electrons in an external electromagnetic field, a non-relativistic current- and spin-density functional theory of Vignale and Rasolt (1987) is generalized to a relativistic current- and spin-density functional theory. A generalized Hohenberg-Kohn theorem is shown to hold, and a single-particle equation of the Kohn-Sham-Dirac type is derived.By choosing the charge density and the magnetization density as the two basic variables, a single-particle equation is derived in a form suitable to an isolated atom or ion. In the single-particle equation, the magnetic interaction is expressed in a form similar to the Zeeman term in which the spin and the orbital angular momenta couple with an effective magnetic field. The effect of the orbital current is included implicitly through the spin-orbit interaction and explicitly through the Zeeman term in which the spin and the orbital angular momenta couple with an effective magnetic field. The effective magnetic field is given by the variation of the exchange and correlation energy functional with respect to the magnetization density that consists of the spin and the orbital angular momentum density, and should be determined self-consistently. The single-particle equation is applied to an atomic structure calculation for the trivalent ions of the lanthanide series, and the total spin and the orbital angular momenta are found to obey Hund's rules well.This new theoretical scheme provides a good basis for a quantitative calculation of the electronic structure for the f-electron systems.

为了计算 f 电子化合物的电子结构，其中 f 电子是巡回的并负责磁性，除了相对论效应之外，还需要考虑源自自旋极化和轨道电流的磁效应。对于外部电磁场中相互作用的电子系统，Vignale 和 Rasolt (1987) 的非相对论电流和自旋密度泛函理论被推广为相对论电流和自旋密度泛函理论。证明了广义Hohenberg-Kohn定理成立，并推导了Kohn-Sham-Dirac型单粒子方程。选择电荷密度和磁化强度作为两个基本变量，推导了单粒子方程以适合孤立原子或离子的形式。在单粒子方程中，磁相互作用以类似于塞曼项的形式表示，其中自旋和轨道角动量与有效磁场耦合。轨道电流的影响通过自旋轨道相互作用隐式包含在内，并通过塞曼项显式包含，其中自旋和轨道角动量与有效磁场耦合。有效磁场由交换和相关能函数相对于由自旋和轨道角动量密度组成的磁化密度的变化给出，并且应该自洽地确定。将单粒子方程应用于镧系三价离子的原子结构计算，发现总自旋和轨道角动量很好地服从洪德定律。这一新的理论方案为定量计算提供了良好的基础。 f 电子系统的电子结构。