Resonant Dative Bonds

Abstract The dative bond is an often underappreciated entity in the theory of chemical interactions, despite its explanatory and predictive potential. In this work, the concept is recovered to computationally design a novel resonant dative bonding pattern in ring molecules, which would be formally considered to be composed of multiple hypervalent and hypovalent atoms. Starting with the (HCPO) 3 ring arranged as alternating carbons and phosphorus, we propose that the major Lewis structure is composed of P═O double bonds and “semi‐dative‐semi‐covalent” P─C bonds. The three carbons technically are a rare case of σ 0 π 2 carbenes; however, due to the stability granted by the delocalized, resonant dative bonds, we termed them “ pseudo‐carbenes ”. By experimenting with isoelectronic systems with other elements but with the same bonding pattern, we also observed pseudo‐nitrenes, pseudo‐silylenes, and dicoordinated halogens, among other unusual structures. Surprisingly, the isomeric rings with normal valence and traditional covalent bonds were found to be of much higher energy, suggesting that the resonant dative bonds can potentially be a source of highly stable molecular entities.