Si ← N Dative Tetrel Bonding in Anionic Bis(catecholato)silicates: Role of Local Electronic Anisotropy

, indicating the formation of energetically favorable donor-acceptor interactions that persist even after accounting for substantial monomer deformation. Analysis of the electron density redistribution accompanying complex formation reveals that the Si ← N contact occupies an intermediate regime between weak noncovalent interactions and classical covalent bonding, consistent with a closed-shell dative interaction dominated by directionality and orbital alignment. The interaction strength is found to be highly sensitive to remote electronic substitution, with stronger nitrogen donors and more electron-withdrawing catecholate substituents enhancing the electrophilic character of the silicon center. Overall, these results show that local electronic features can dominate over formal molecular charge, enabling tunable dative tetrel bonding in hypercoordinate anionic silicon systems.