Resonant Dative Bonds.

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Chemical Bonding Theory

Background:

• Dative bonds are crucial in chemical interactions but often underappreciated.
• Understanding dative bonding can unlock novel molecular designs.
• Hypervalent and hypovalent atoms present unique bonding challenges.

Purpose of the Study:

• To computationally design a novel resonant dative bonding pattern in ring molecules.
• To explore the stability and properties of molecules featuring these novel bonding patterns.
• To investigate the potential of resonant dative bonds in creating stable molecular entities.

Main Methods:

• Computational design of ring molecules, specifically the (HCPO)3 ring.
• Analysis of Lewis structures, focusing on P═O double bonds and P─C semi-dative-semi-covalent bonds.
• Exploration of isoelectronic systems to identify other unusual structures like pseudo-nitrenes and pseudo-silylenes.

Main Results:

• A novel resonant dative bonding pattern was designed in the (HCPO)3 ring.
• Carbons in the ring were identified as rare σ0π2 carbenes, termed "pseudo-carbenes" due to stabilization by delocalized dative bonds.
• Isoelectronic systems revealed other unusual structures, including pseudo-nitrenes and dicoordinated halogens.
• Resonant dative bonded rings were found to be more stable than isomeric rings with traditional covalent bonds.

Conclusions:

• Resonant dative bonds can lead to highly stable molecular entities.
• The concept of dative bonding offers significant explanatory and predictive potential in chemistry.
• This work introduces a new perspective on chemical bonding, challenging traditional valence rules.