Na_8和Na_{20}团簇热力学的从头算电子结构研究
Thermodynamics of Na_8 and Na_{20} clusters studied with ab-initio electronic structure methods
摘要：
采用多重直方图方法和密度泛函理论中的价电子从头计算方法研究了Na_8和Na_{20}团簇的热力学性质。我们考虑了各种电子动能泛函和赝势对正则离子比热的影响。我们考虑的所有模型的结果显示出定性的相似性，但也显着的温度变化从模型到模型的峰值和比热曲线中的其他功能。与从头算结果相比，使用唯象赝势使熔融峰大幅度移动（~ 50- 100 K）。有人认为，选择一个好的赝势和使用更好的电子动能泛函有潜力进行大的时间尺度和大尺寸的团簇的模拟。
英文摘要：
We study the thermodynamics of Na_8 and Na_{20} clusters using multiple-histogram methods and an ab initio treatment of the valence electrons within density functional theory. We consider the influence of various electron kinetic-energy functionals and pseudopotentials on the canonical ionic specific heats. The results for all models we consider show qualitative similarities, but also significant temperature shifts from model to model of peaks and other features in the specific-heat curves. The use of phenomenological pseudopotentials shifts the melting peak substantially (~ 50--100 K) when compared to ab-initio results. It is argued that the choice of a good pseudopotential and use of better electronic kinetic-energy functionals has the potential for performing large time scale and large sized thermodynamical simulations on clusters.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
