CEA-UJF, Institute for Nanosciences and Cryogenics, SP2M/L_Sim, 38054, Grenoble, Cedex 9, France.
Phys Rev Lett. 2010 Nov 19;105(21):216408. doi: 10.1103/PhysRevLett.105.216408.
We use Fermi-liquid relations to address the accuracy of conductances calculated from the single-particle states of exact Kohn-Sham (KS) density functional theory. We demonstrate a systematic failure of this procedure for the calculation of the conductance, and show how it originates from the lack of renormalization in the KS spectral function. In certain limits this failure can lead to a large overestimation of the true conductance. We also show, however, that the KS conductances can be accurate for single-channel molecular junctions and systems where direct Coulomb interactions are strongly dominant.
我们利用费米液体关系来研究从精确的 Kohn-Sham（KS）密度泛函理论的单粒子态计算得到的电导的准确性。我们展示了这种方法在计算电导时的系统失败，并说明了它是如何源于 KS 谱函数中缺乏重整化的。在某些极限下，这种失败可能导致对真实电导的过大估计。然而，我们还表明，KS 电导对于单通道分子结和直接库仑相互作用占主导地位的系统来说是准确的。
