Perdew–Zunger self-interaction correction (PZSIC) reintroduces an exact constraint to approximate density functional theory (DFT). However, PZSIC can paradoxically degrade performance, and standard DFT approximations (with or without PZSIC) are not systematically improvable. We use the adiabatic projection formalism (Janesko, B. G. J. Chem. Phys.2022, 156, 014111, https://doi.org/10.1063/5.0076144) to derive PZSIC in terms of a reference system experiencing only electron self-interaction. Generalization to a “self-and-some-others” interaction introduces correlation into the reference system, systematically bridging from PZSIC to exact wave function theory without the double counting of correlation. Minimal active spaces accurately treat nearly one electron, near-equilibrium, and strongly correlated model systems at modest computational expense.

中文翻译：

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自相互作用校正密度泛函理论的系统改进推广

Perdew-Zunger 自交互校正 (PZSIC) 重新引入了近似密度泛函理论 (DFT) 的精确约束。然而，PZSIC 会自相矛盾地降低性能，并且标准的 DFT 近似（有或没有 PZSIC）不能系统地改进。我们使用绝热投影形式（Janesko, BG J. Chem. Phys. 2022, 156, 014111, https://doi.org/10.1063/5.0076144) 根据仅经历电子自相互作用的参考系统推导出 PZSIC。对“自我和他人”相互作用的概括将相关性引入参考系统，系统地将 PZSIC 桥接到精确波函数理论，而无需重复计算相关性。最小活动空间以适度的计算成本准确地处理近一个电子、近平衡和强相关模型系统。