Trans-Influence in Dinuclear Pt(III) Complexes: Electronic Structure, σ-Donation, and Pt-Pt Spin-Spin Coupling

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Materials Science

Background:

• Dinuclear platinum(III) complexes exhibit unique electronic properties.
• Understanding trans influence is crucial for designing novel materials and catalysts.
• Ligand effects on metal-metal bonds require detailed investigation.

Purpose of the Study:

• To investigate the trans influence in pivalamidate-bridged dinuclear platinum(III) complexes.
• To quantify the propagation of ligand-metal interactions through the Pt-Pt bond.
• To elucidate the effects on bond polarization, axial water coordination, and ¹J_PtPt spin-spin coupling constants.

Main Methods:

• Ab initio molecular dynamics simulations.
• Natural localized molecular orbital (NLMO) analysis.
• Systematic variation of axial ligand σ-donation strength.

Main Results:

• Strong σ-donating ligands quantitatively polarize the Pt-Pt bond, shifting electron density.
• Bond polarization is identified as the primary cause for reduced ¹J_PtPt coupling.
• Polarization induces a Pt^IV-Pt^II-like mixed-valence character, destabilizing axial water coordination.

Conclusions:

• Ligand σ-donation significantly impacts electronic structure and bonding in dinuclear platinum(III) complexes.
• The trans influence mechanism is elucidated through detailed electronic structure analysis.
• Findings provide insights into the rational design of platinum-based materials with tunable properties.