Rethinking polyiodides: the role of electron-deficient multicenter bonds

Area of Science:

• Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Polyiodides possess a rich bicentennial history with ongoing interest due to complex chemical bonding.
• Recent advancements in halogen bonding and supramolecular interactions have renewed focus on polyiodide systems.
• Materials research highlights the link between local bonding details and macroscopic properties in polyiodides.

Purpose of the Study:

• To present a novel bonding scheme for polyiodides utilizing electron-deficient multicenter bonds (EDMBs).
• To offer a revised Lewis dot formula approach for clearer pen-and-paper understanding of polyiodide bonding.
• To demonstrate the general applicability of the model to related polyhalide systems.

Main Methods:

• Reinterpretation of polyiodide bonding through a new theoretical model.
• Application of revised Lewis dot formulas to visualize bonding.
• Generalization of the model to polyiodonium cations and other polyhalides.

Main Results:

• The proposed EDMB model provides a clearer understanding of polyiodide bonding.
• The model offers insights into fundamental concepts like hypervalency versus hypercoordination.
• Distinctions between covalent bonds and supramolecular interactions are clarified.

Conclusions:

• The EDMB model offers a valuable alternative perspective on polyiodide chemistry.
• This approach enhances understanding of secondary and halogen bonds within these systems.
• The model's generalizability supports its application across various polyhalide research areas.