Parameter-free exchange functional
Parameter-free exchange functional
复制标题
无参数交换功能
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
K. Hirao
中科院分区：
文献类型：
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作者：
T. Tsuneda;K. Hirao
传统的广义梯度近似的交换能推导出遵守的基本条件的确切交换功能。我们提出了一个简单的分析交换功能，不包含半经验参数或调整的基本常数。我们表明，这个功能满足几个重要的和严格的基本条件，并给出准确的交换能量的原子，氢通过氩，误差范围内的百分之几。它可以针对任何种类的动能密度进行更新。令人惊讶的是，目前的形式正好给出了缓慢变化的密度梯度膨胀系数。
Conventional generalized-gradient approximations for exchange energy are derived to obey the fundamental conditions of the exact exchange functional. We present a simple analytic exchange functional that does not contain a semiempirical parameter or an adjusted fundamental constant. We show that this functional satisfies several significant and strict fundamental conditions, and gives accurate exchange energies for the atoms, hydrogen through argon, within a margin of error of a few percent. It can be updated for any kind of kinetic-energy density. Surprisingly, the present formalism exactly gives the gradient expansion coefficient for slowly varying density.