论文标题
确认PPLB导数不连续性：模型系统有限温度下的精确化学潜力
Confirmation of the PPLB derivative discontinuity: Exact chemical potential at finite temperatures of a model system
论文作者
论文摘要
1982年具有里程碑意义的Perdew，Parr，Levy和Balduz（通常称为PPLB）的论文为我们对衍生性不连续性在密度功能理论中的作用的现代理解奠定了基础，这驱动了大量发展以说明其影响。在消失温度下化学潜力的一个简单模型在其论证中起着至关重要的作用。我们在最简单的非平凡系统中研究了该模型的有效性，可以将其应用于该模型，并且可以很容易地求解Hubbard Dimer。我们在关键的零温度极限中发现了确切的一致性，并表明该模型在大量温度范围内保持准确。我们确定该范围如何取决于相关的强度。我们将模型扩展到近似于衍生词不连续性的近似自由能，这是标准半局部近似值中缺少的特征。我们对此近似值提供了校正，以产生更准确的自由能。我们讨论了这些结果与温暖的物质的相关性。
The landmark 1982 paper of Perdew, Parr, Levy, and Balduz (often called PPLB) laid the foundation for our modern understanding of the role of the derivative discontinuity in density functional theory, which drives much development to account for its effects. A simple model for the chemical potential at vanishing temperature played a crucial role in their argument. We investigate the validity of this model in the simplest non-trivial system to which it can be applied and which can be easily solved exactly, the Hubbard dimer. We find exact agreement in the crucial zero-temperature limit, and show the model remains accurate for a significant range of temperatures. We identify how this range depends on the strength of correlations. We extend the model to approximate free energies accounting for the derivative discontinuity, a feature missing in standard semi-local approximations. We provide a correction to this approximation to yield even more accurate free energies. We discuss the relevance of these results for warm dense matter.
