title: Exploring the molecular structure of imidazolium-silica-based nanoparticle networks by combining solid-state NMR spectroscopy and first-principles calculations.
abstract: 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. (11)B and (31)P HETCOR CP MAS experiments were recorded. Calculated (19)F NMR 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 π-π stacking between the IM rings are presented. The predicted electronic properties confirm the photoluminescence emissions in the correct spectral domain.
authors.affiliation: Vienna University of Technology, Institute of Materials Chemistry, 1060 Vienna (Austria); Physics of Condensed Matter (PMC), Ecole Polytechnique, 91128 Palaiseau (France). marie-alexandra.neouze@polytechnique.edu.
authors.forename: Marie-Alexandra
authors.initials: MA
authors.lastname: Neouze
authors.forename: Martin
authors.initials: M
authors.lastname: Kronstein
authors.forename: Marco
authors.initials: M
authors.lastname: Litschauer
authors.forename: Michael
authors.initials: M
authors.lastname: Puchberger
authors.forename: Cristina
authors.initials: C
authors.lastname: Coelho
authors.forename: Christian
authors.initials: C
authors.lastname: Bonhomme
authors.forename: Christel
authors.initials: C
authors.lastname: Gervais
authors.forename: Frederik
authors.initials: F
authors.lastname: Tielens
keywords: NMR spectroscopy; density functional calculations; luminescence; nanoparticles; surface chemistry