Zr4+ solution structures from pair distribution function analysis

The structures of metal ions in solution constitute essential information for obtaining chemical insight spanning from catalytic reaction mechanisms to formation of functional nanomaterials. Here, we explore Zr4+ solution structures using X-ray pair distribution function (PDF) analysis across pH (0-14), concentrations (0.1-1.5 M), solvents (water, methanol, ethanol, acetonitrile) and metal sources (ZrCl4, ZrOCl2 center dot 8H(2)O, ZrO(NO3)(2)center dot xH(2)O). In water, [Zr-4(OH)(8)(OH2)(16)](8+)-tetramers are predominant, while non-aqueous solvents contain monomeric complexes. The PDF analysis also reveals second sphere coordination of chloride counter ions to the aqueous tetramers. The results are reproducible across data measured at three different beamlines at the PETRA-III and MAX IV synchrotron light sources.

Automated summary

The structures of Zr4+ ions in solution were studied using X-ray pair distribution function (PDF) analysis. It was found that [Zr-4(OH)8(OH2)16]8+ tetramers are predominant in water, while monomeric complexes exist in non-aqueous solvents. The PDF analysis also revealed second sphere coordination of chloride counter ions to the aqueous tetramers.