Si-H···Se Chalcogen-Hydride Bond Quantified by Diffraction and Topological Analyses.

Area of Science:

• Solid-state chemistry
• Quantum chemistry
• Crystallography

Background:

• Investigating noncovalent interactions is crucial for understanding molecular behavior.
• The Si-H···Se contact in 1-mesitylselanyl-8-(dimethylsilyl)naphthalene presents a unique spatial arrangement.
• Distinguishing between enforced proximity and favorable interactions requires detailed analysis.

Purpose of the Study:

• To investigate the nature of the Si-H···Se contact in the specified naphthalene derivative.
• To determine if the observed interaction is a consequence of steric constraints or a favorable bonding phenomenon.
• To quantify the properties and elucidate the origin of this noncovalent interaction.

Main Methods:

• High-resolution X-ray diffraction data collection.
• Multipole refinement of the crystal structure.
• Topological analysis using Bader's quantum theory of atoms in molecules (QTAIM).
• Comparison with computational parameters and related bonding types.

Main Results:

• Charge density studies provided detailed insights into the Si-H···Se interaction.
• Topological analysis confirmed the noncovalent nature of the contact.
• The interaction was quantitatively characterized and compared to other bonding models.

Conclusions:

• The Si-H···Se interaction is not merely due to steric hindrance but represents a favorable bonding.
• The interaction is best classified as a chalcogen-hydride bond.
• This classification is supported by comparisons with Si-H···[M] agostics, hydride bonding, and chalcogen bonds.