The simplest, algebraic quantum-electrodynamical corrections, due to the double-negative energy subspace and instantaneous interactions, are computed to the no-pair energy of two-spin-1/2-fermion systems. Numerical results are reported for two-electron atoms with a clamped nucleus and positronium-like genuine two-particle systems. The Bethe-Salpeter equation provides the theoretical framework, and numerical methods have been developed for its equal-time time-slice. In practice, it requires solving a sixteen-component eigenvalue equation with a two-particle Dirac Hamiltonian, including the appropriate interaction. The double-pair corrections can either be included in the interaction part of the eigenvalue equation or treated as a perturbation to the no-pair Hamiltonian. The numerical results have an $α$ fine-structure constant dependence that is in excellent agreement with the known $α^3E_\mathrm{h}\$-order double-pair correction of non-relativistic quantum electrodynamics.
Variational Dirac-Coulomb explicitly correlated computations for atoms and molecules
正能量投影的狄拉克-库仑方程求解使用显式相关高斯函数。该算法和计算程序的目的是一个十亿分之一的能量收敛，提供一个起点，进一步比较和进一步发展与高分辨率原子和分子光谱。除了详细讨论的基本旋量结构，置换和点群对称性的实施，各种选项的正能量投影程序。收敛到十亿分之几精度的无对狄拉克-库仑能量与小核电荷数的原子和分子系统的微扰结果进行了比较。第二篇论文[D。Ferenc，P. Jeszenszki，and E. Mátyus（2022）]描述了Breit交互作用在这个框架中的实现。
Unsymmetrical and symmetrical one-range addition theorems for Slater type orbitals and Coulomb-Yukawa like correlated interaction potentials of integer and noninteger indices
Relativistic density functional theory with finite-light-speed correction for the Coulomb interaction: a non-relativistic-reduction based approach
在局域密度近似下的非相对论约化的密度泛函理论（DFT）中引入Breit修正，即对$ O \left( 1/ c^2 \right) $中电子-电子相互作用的库仑相互作用的有限光速修正.利用这种新发展的相对论密度泛函理论，发现镧原子最外层的电子可能是$ p $轨道而不是$ d $轨道，这与以前基于波函数理论的计算结果一致.对第一电离能的反常行为给出了可能的解释。该密度泛函方法为超重元素性质的研究提供了一种实用的计算方法。
Evaluation of potential energy of interaction between molecules using one-range addition theorems for Slater type orbitals and Coulomb-Yukawa like correlated interaction potentials
