Exploring the Molecular Structure of Imidazolium–Silica-Based Nanoparticle Networks by Combining Solid-State NMR Spectroscopy and First-Principles Calculations

A DFT-based molecular model for imidazolium-silica-based nanoparticle networks (INNs) is presented. The INNs were synthesized and characterized by using small-angle X-ray scattering (SAXS), NMR spectroscopy, and theoretical ab initio calculations. B-11 and P-31 HETCOR CP MAS experiments were recorded. Calculated (FNMR)-F-19 spectroscopy results, combined with the calculated anion-imidazolium (IM) distances, predicted the IM chain density in the INN, which was also confirmed from thermogravimetric analysis/mass spectrometry results. The presence of water molecules trapped between the nanoparticles is also suggested. First considerations on possible - stacking between the IM rings are presented. The predicted electronic properties confirm the photoluminescence emissions in the correct spectral domain.