Can Dative Bond Between Two Anions Possible?

Area of Science:

• Inorganic Chemistry
• Theoretical Chemistry
• Quantum Chemistry

Background:

• Chemical bond formation typically occurs between oppositely charged species.
• Interactions between similarly charged fragments are usually non-covalent.
• The formation of a genuine covalent bond between anions was considered highly improbable.

Purpose of the Study:

• To investigate the possibility of forming a dative covalent bond between two anionic fragments.
• To computationally determine the strength and nature of the H₃Be⁻←X⁻ interaction.
• To assess the potential for experimental observation of this novel chemical bond.

Main Methods:

• Utilized ab initio coupled cluster theory for high-level electronic structure calculations.
• Calculated the electronic properties and bond dissociation energies for H₃Be⁻←X⁻ systems.
• Modeled the interaction in the presence of polar solvents to simulate experimental conditions.

Main Results:

• Demonstrated the formation of a strong dative covalent bond between H₃Be⁻ and various anionic fragments (X⁻ = CH₃⁻, CN⁻, OH⁻, F⁻).
• Quantified significant bond dissociation energies, indicating a robust interaction.
• The calculations revealed an unprecedented stabilization through this dative covalent linkage.

Conclusions:

• The study presents the first evidence of a strong dative covalent bond formed between two anionic species.
• The calculated bond strengths suggest that these novel chemical entities are potentially observable experimentally.
• This finding challenges conventional understanding of chemical bonding involving like-charged fragments.