Positron binding to molecules is key to extremely enhanced positron annihilation and positron-based molecular spectroscopy¹. Although positron binding energies have been measured for about 90 polyatomic molecules^1,2,3,4,5,6, an accurate ab initio theoretical description of positron–molecule binding has remained elusive. Of the molecules studied experimentally, ab initio calculations exist for only six; these calculations agree with experiments on polar molecules to at best 25 per cent accuracy and fail to predict binding in nonpolar molecules. The theoretical challenge stems from the need to accurately describe the strong many-body correlations including polarization of the electron cloud, screening of the electron–positron Coulomb interaction and the unique process of virtual-positronium formation (in which a molecular electron temporarily tunnels to the positron)¹. Here we develop a many-body theory of positron–molecule interactions that achieves excellent agreement with experiment (to within 1 per cent in cases) and predicts binding in formamide and nucleobases. Our framework quantitatively captures the role of many-body correlations and shows their crucial effect on enhancing binding in polar molecules, enabling binding in nonpolar molecules, and increasing annihilation rates by 2 to 3 orders of magnitude. Our many-body approach can be extended to positron scattering and annihilation γ-ray spectra in molecules and condensed matter, to provide the fundamental insight and predictive capability required to improve materials science diagnostics^7,8, develop antimatter-based technologies (including positron traps, beams and positron emission tomography)^8,9,10, and understand positrons in the Galaxy¹¹.

正电子与分子结合是极其增强的正电子湮灭和基于正电子的分子光谱¹的关键。尽管已经测量了大约 90 个多原子分子^{1、2、3、4、5、6的正电子结合能}，正电子 - 分子结合的准确从头算理论描述仍然难以捉摸。在实验研究的分子中，从头计算仅存在六个；这些计算与极性分子的实验相一致，准确率最高为 25%，但无法预测非极性分子的结合。理论挑战源于需要准确描述强多体相关性，包括电子云的极化、电子-正电子库仑相互作用的筛选和虚拟正电子形成的独特过程（其中分子电子暂时隧道到正电子）¹. 在这里，我们开发了一种正电子-分子相互作用的多体理论，该理论与实验取得了极好的一致性（在某些情况下达到了 1% 以内），并预测了甲酰胺和核碱基的结合。我们的框架定量地捕捉了多体相关性的作用，并显示了它们对增强极性分子结合、实现非极性分子结合以及将湮灭率提高 2 到 3 个数量级的关键作用。我们的多体方法可以扩展到分子和凝聚态物质中的正电子散射和湮灭 γ 射线光谱，以提供改进材料科学诊断^7,8所需的基本洞察力和预测能力，开发基于反物质的技术（包括正电子陷阱） ，光束和正电子发射断层扫描）^8,9,10，并了解 Galaxy ¹¹中的正电子。