Calculation of the Band Structure for Copper as a Function of Lattice Spacing
Calculation of the Band Structure for Copper as a Function of Lattice Spacing
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计算铜的能带结构作为晶格间距的函数
DOI：
10.1103/physrev.167.601
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发表时间：
1968
期刊：
影响因子：
--
通讯作者：
H. W. Joy
中科院分区：
文献类型：
--
作者：
H. L. Davis;J. Faulkner;H. W. Joy
本文描述了铜的电子能带结构随晶格间距变化的计算。计算使用先前描述的基于Korringa-Kohn-Rostoker带理论计算方法的恒定能量搜索技术进行。结果包括三个费米表面上的26,066个点，分别对应晶格间距$a$, $0.995a$和$0.99a$，其中$a$为铜的标准晶格常数。利用体积可压缩性的测量值，计算出费米表面随压力的变化，与最近的de Haas-van Alphen实验结果非常吻合。计算结果也与反射率测量的压力依赖性以及与费米能量处态密度的压力依赖性相关的热力学实验相一致。这些结果是基于利用自由原子电荷密度和斯莱特交换计算得到的电势的能带结构。当考虑未压缩的金属时，发现当使用不同的自由原子电荷密度时，该处方会产生具有广泛变化的能带结构的电位。然而，一旦发现了自由原子电荷密度，可以为未压缩的金属产生相当精确的势，我们从目前的结果中得出结论，势处方似乎非常有希望准确地描述金属能带结构随晶格间距变化的变化。
Calculations are described which relate to the change in the electronic band structure of copper with change in lattice spacing. The calculations were performed using previously described constant-energy search techniques based on the Korringa-Kohn-Rostoker method for band-theory calculations. Included in the results are a total of 26 066 points on each of three Fermi surfaces corresponding to lattice spacings $a$, $0.995a$, and $0.99a$, with $a$ being the normal lattice constant of copper. Using the measured value for the volume compressibility, our results give calculated changes in the Fermi surface with pressure which agree very well with recent de Haas-van Alphen experimental results. The calculated results are also consistent with the pressure dependence of reflectivity measurements, and with experiments thermodynamically related to the pressure dependence of the density of states at the Fermi energy. These results are based on band structures obtained from potentials calculated by a commonly invoked prescription using free-atom charge densities and Slater exchange. When considering the uncompressed metal, this prescription has been found to generate potentials giving widely varying band structures when different free-atom charge densities are used. However, once free-atom charge densities have been found which generate a reasonably accurate potential for the uncompressed metal, we conclude from the present results that the potential prescription appears to be very promising in its ability to accurately describe changes in metallic band structures with changes in lattice spacing.