arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2111.09652cond-mat.mtrl-sci
收藏

对称保持最大投影Wannier函数

Symmetry Conserving Maximally Projected Wannier Functions

K. Koepernik, O. Janson, Yan Sun, J. van den Brink

AI总结:

本文在FPLO代码中实现了对称保持最大投影Wannier函数(SCMPWF)方法,通过投影和正交化获得满足空间群对称性的高度局域化Wannier函数,并讨论了Berry联络与位置算符的相互作用及性能。

摘要:

为了从基于修正平面波基的高度精确密度泛函理论代码中获得局域描述,需要变换到局域正交Wannier函数基。在强制执行空间群对称性约束的同时实现这一目标,对称保持最大投影Wannier函数(SCMPWF)方法已在全势局域轨道代码FPLO中实现。SCMPWF表示最大局域化Wannier函数的零阶近似,将波函数子集投影到一组适当选择的局域试探函数上,随后进行正交化。FPLO中局域轨道的特殊性质使其成为理想的投影子集合,因为它们被构造为化学基。虽然在许多情况下投影到FPLO基轨道上就足够了,但也可以选择特定的局域线性组合作为投影子,以处理键中心Wannier函数的情况。这一选择被证明能产生高度局域化的Wannier函数,这些函数通过构造满足晶体的空间群对称性。此外,我们讨论了Berry联络与位置算符之间的相互作用,特别是其可能的近似、对称性以及在基不明确情况下Bloch和相位规范的最优选择。我们还介绍了通过FPLO实现SCMPWF可访问的各种功能,讨论并比较了性能,并提供了示例应用。

英文摘要:

To obtain a local description from highly accurate density functional theory codes that are based on modified plane wave bases, a transformation to a local orthonormal Wannier function basis is required. In order to do so while enforcing the constraints of the space group symmetry the Symmetry Conserving Maximally Projected Wannier Functions (SCMPWF) approach has been implemented in the Full-Potential-Local-Orbital code, FPLO. SCMPWFs represent the zeroth order approximation to maximally localized Wannier functions, projecting a subset of wave functions onto a set of suitably chosen local trial-functions with subsequent orthonormalization. The particular nature of the local orbitals in FPLO make them an ideal set of projectors, since they are constructed to be a chemical basis. While in many cases projection onto the FPLO basis orbitals is sufficient, the option is there to choose particular local linear combinations as projectors, in order to treat cases of bond centered Wannier functions. This choice turns out to lead to highly localized Wannier functions, which obey the space group symmetry of the crystal by construction. Furthermore we discuss the interplay of the Berry connection and position operator and especially its possible approximation, symmetries and the optimal choice of Bloch sum phase gauge in cases where the basis is not explicitly known. We also introduce various features which are accessible via the FPLO implementation of SCMPWFs, discuss and compare performance and provide example applications.

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。

↑