论文标题
磁性转换总和规则和分子浆果曲率的近似模型
Magnetic-Translational Sum Rule and Approximate Models of the Molecular Berry Curvature
论文作者
论文摘要
浆果连接和曲率是磁场中原子和分子的电子结构计算的关键组成部分。它们确保在这些环境中分子动力学期间有效的核哈密顿量和正确的质量运动的正确翻译行为。在这项工作中，我们演示了浆果连接和曲率的这些特性是如何来自电子波函数的翻译对称性以及如何通过伦敦轨道的有限基集（而不是通过标准高斯基集组）完全捕获的。这是通过在不同基础集中的小分子上进行的一系列Hartree-Fock计算来说明的。基于浆果曲率作为电子对核的屏蔽的产生的物理解释，我们使用电子密度的Mulliken碎片化方案介绍和测试一系列近似值。这些近似值将在磁场中的从头算分子动力学计算中特别有用，因为它们降低了计算成本，同时恢复了正确的物理学和多达95％的确切浆果曲率。
The Berry connection and curvature are key components of electronic structure calculations for atoms and molecules in magnetic fields. They ensure the correct translational behavior of the effective nuclear Hamiltonian and the correct center-of-mass motion during molecular dynamics in these environments. In this work, we demonstrate how these properties of the Berry connection and curvature arise from the translational symmetry of the electronic wave function and how they are fully captured by a finite basis set of London orbitals but not by standard Gaussian basis sets. This is illustrated by a series of Hartree-Fock calculations on small molecules in different basis sets. Based on the resulting physical interpretation of the Berry curvature as the shielding of the nuclei by the electrons, we introduce and test a series of approximations using the Mulliken fragmentation scheme of the electron density. These approximations will be particularly useful in ab initio molecular dynamics calculations in a magnetic field, since they reduce the computational cost, while recovering the correct physics and up to 95% of the exact Berry curvature.
