The affinity of AtO⁺ for around 20 model ligands (L), carrying functionalized oxygen, sulfur, and nitrogen atoms, has been assessed through a combined experimental and theoretical methodology. Significant equilibrium constants (K_L ∼ 10⁴) have been measured for sulfur-containing compounds, in agreement with the previously highlighted, relatively stable radiolabeling of SH-containing proteins with ²¹¹At. Conversely, no interaction occurs in the aqueous phase for their oxygenated counterparts, but higher affinities (K_L > 10⁶) have been determined for nitrogen-based ligands, including aromatic nitrogen heterocycles. The quantum mechanical calculations definitively ruled out any rationale based on either the metallic character of astatine or its guessed softness; the favored interactions all involve specifically the oxygen atom of AtO⁺, leading to the formation of covalent O–S or O–C single bonds.

中文翻译：

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质疑亲电子A对含硫化合物的亲和力：揭示了意外的结合。

通过组合的实验和理论方法，评估了AtO ⁺对约20个带有官能化氧，硫和氮原子的模型配体（L）的亲和力。显著平衡常数（ķ_大号〜10 ⁴）已经被测量含硫化合物，在协议与先前突出显示的，相对稳定的含有SH基的蛋白与放射性标记²¹¹在。相反，对于含氧化合物，在水相中没有相互作用，但亲和力更高（K _L > 10 ⁶已经确定了基于氮的配体，包括芳族氮杂环。量子力学计算绝对地基于on的金属特性或其推测的柔软度排除了任何理由。所有有利的相互作用都特别涉及AtO ⁺的氧原子，从而导致形成共价的OS或OC单键。