This manuscript combines a search in the Cambridge Structural Database (CSD) and theoretical density functional theory (DFT) calculations to analyse the existence and importance of charge assisted pnictogen and halogen bonds involving halophosphonium cations. Trivalent pnictogen atoms typically have three σ-holes and are able to establish up to three pnictogen bonds (PnBs). In phosphonium salts, the phosphorus atom forms four covalent bonds and, consequently, four σ-holes are located at the extension of these bonds. Therefore, up to four charge assisted PnBs can be formed between these holes and the counterions or any electron rich atom. The covalent bond arrangement around the phosphorus atom is similar to that around tetravalent tetrel atoms and converts into a similar pattern of σ-hole interactions. We have found and described this type of charge assisted pnictogen bond in various halophosphonium crystal structures. Moreover, the competition of charge assisted PnBs with charge assisted halogen bonds (HaBs) has been also studied both theoretically and by analysing the CSD.

中文翻译：

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电荷辅助的卤素和光原键：来自剑桥结构数据库和DFT计算的见解

该手稿结合了在剑桥结构数据库（CSD）和理论密度泛函理论（DFT）计算中的搜索结果，以分析涉及卤phosph阳离子的电荷辅助光子和卤素键的存在和重要性。三价光子原子通常具有三个σ孔，最多可以建立三个光子键（PnBs）。在phospho盐中，磷原子形成四个共价键，因此，四个σ孔位于这些键的延伸位置。因此，在这些孔与抗衡离子或任何富电子原子之间最多可形成四个电荷辅助PnB。磷原子周围的共价键排列与四价t原子之间的共价键排列相似，并转换为类似的σ-孔相互作用模式。我们已经发现并描述了各种卤代磷鎓晶体结构中的这种电荷辅助光子原键。此外，在理论上和通过分析CSD，还研究了带有电荷辅助卤素键（HaBs）的电荷辅助PnB的竞争。