论文标题
相对论量子化学的精确两组分哈密顿人：两电子图片变化校正变得简单
Exact two-component Hamiltonians for relativistic quantum chemistry: Two-electron picture-change corrections made simple
论文作者
论文摘要
基于自一致的字段（SCF）原子平均场（AMF）数量，我们提出了两个简单但有效且数值准确的矩阵algebraic方法，以纠正在一个确切的两种效果（pce）中的标量 - textit {and} spin-orbit spin-orbit spinit {and} spin-orbit spin-orptian spectian（pce）的构造（pce）。这两种方法都称为AMFX2C和E（Xtended）AMFX2C，使我们能够独特地量身定制PCE校正，以授予均值模型，即$ $ hartree-fock或kohn-sham dft，在后一种情况下，也避免了对交换式PCE校正的重点计算。我们评估了这些PCE校正模型在组-18（封闭壳）和组16（开孔）二元分子的旋转能量上的数值性能，与参考四组分数据相比，与参考四组分数据相比，达到了一致的$ \！10^{ - 5} $ HARTREE精度。其他测试包括SCF计算分子特性的计算，例如绝对接触密度和氟氟化物化合物中的接触密度转移（CNF $ _ {n} $，n = 2,4,6），以及X射线核心电源$ 5D $ 5D $ -6DD-cor-corm op-6d corm op-6d coct op-6d cor-ccint op Motion耦合群体的计算，我们 数据。总而言之，我们有信心，我们的（E）AMFX2C PCE校正模型构成了通用和可靠的相对论的两组分量子化学方法的基本里程碑，并以其计算成本的一小部分保持了父级四组分的准确性。
Based on self-consistent field (SCF) atomic mean-field (amf) quantities, we present two simple, yet computationally efficient and numerically accurate matrix-algebraic approaches to correct both scalar-relativistic \textit{and} spin-orbit two-electron picture-change effects (PCE) arising within an exact two-component (X2C) Hamiltonian framework. Both approaches, dubbed amfX2C and e(xtended)amfX2C, allow us to uniquely tailor PCE corrections to mean-field models, $viz.$ Hartree-Fock or Kohn-Sham DFT, in the latter case also avoiding the need of a point-wise calculation of exchange-correlation PCE corrections. We assess the numerical performance of these PCE correction models on spinor energies of group-18 (closed-shell) and group-16 (open-shell) diatomic molecules, achieving a consistent $\approx\!10^{-5}$ Hartree accuracy compared to reference four-component data. Additional tests include SCF calculations of molecular properties such as absolute contact density and contact density shifts in copernicium fluoride compounds (CnF$_{n}$, n=2,4,6), as well as equation-of-motion coupled cluster calculations of X-ray core ionization energies of $5d$ and $6d$-containing molecules, where we observe an excellent agreement with reference data. To conclude, we are confident that our (e)amfX2C PCE correction models constitute a fundamental milestone towards a universal and reliable relativistic two-component quantum chemical approach, maintaining the accuracy of the parent four-component one at a fraction of its computational cost.
