Interaction between hydrofluorosilicic acid and 1,10-phenanthroline: Hydrolytic stability of chelate complexes of silicon tetrafluoride with bidentate N-donors

Hexafluorosilicate (LH₂)SiF₆ and the cis-[SiF₄(L)] chelate complex characterized by ¹⁹F NMR are products of reaction between hydrofluorosilicic acid and 1,10-phenanthroline (L). XRD findings show that the structure of (LH₂)SiF₆ is stabilized by NH···F hydrogen bonds (N···F 2.618(4), 2.676(4) Å) and CH···F contacts. The relative resistance of the cis-[SiF₄(L)] complex to hydrolysis is associated with the chelate effect.