title: Solving the Hydrogen and Lithium Substructure of Poly(triazine imide)/LiCl Using NMR Crystallography.
abstract: Poly(triazine imide) with incorporated lithium chloride has recently attracted substantial attention due to its photocatalytic activity for water splitting. However, an apparent H/Li disorder prevents the delineation of structure-property relationships, for example, with respect to band-gap tuning. Herein, we show that through a combination of one- and two-dimensional, multinuclear solid-state NMR spectroscopy, chemical modelling, automated electron diffraction tomography, and an analysis based on X-ray pair distribution functions, it is finally possible to resolve the H/Li substructure. In each cavity, one hydrogen atom is bound to a bridging nitrogen atom, while a second one protonates a triazine ring. The two lithium ions within each cavity are positioned between two nitrogen atoms of neighbouring triazine rings. The thereby induced local dipole moments cause slight buckling of the framework and lateral displacements of the Cl-ions at a coherence length below 2 nm. Nevertheless, the average structure conforms to space group P212121. In this way, we demonstrate that, in particular, the above-mentioned techniques allow for smart interplay in delineating the real structure of PTI/LiCl.
authors.affiliation: Inorganic Chemistry III, University of Bayreuth, 95447, Bayreuth, Germany.
authors.forename: Maria B
authors.initials: MB
authors.lastname: Mesch
authors.affiliation: Inorganic Chemistry III, University of Bayreuth, 95447, Bayreuth, Germany.
authors.forename: Kilian
authors.initials: K
authors.lastname: Bärwinkel
authors.affiliation: Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg University Mainz, Jakob-Welder-Weg 11, 55128, Mainz, Germany.
authors.forename: Yaşar
authors.initials: Y
authors.lastname: Krysiak
authors.affiliation: Tectospin, Institut Lavoisier de Versailles (ILV), UMR CNRS 8180, Université de Versailles Saint-Quentin-en-Yvelines, 45 Avenue des Etats-Unis, 78035, Versailles cedex, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Martineau
authors.affiliation: Tectospin, Institut Lavoisier de Versailles (ILV), UMR CNRS 8180, Université de Versailles Saint-Quentin-en-Yvelines, 45 Avenue des Etats-Unis, 78035, Versailles cedex, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Taulelle
authors.affiliation: Lehrstuhl für Kristallographie und Strukturphysik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 3, 91058, Erlangen, Germany.
authors.forename: Reinhard B
authors.initials: RB
authors.lastname: Neder
authors.affiliation: Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg University Mainz, Jakob-Welder-Weg 11, 55128, Mainz, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Kolb
authors.affiliation: Inorganic Chemistry III, University of Bayreuth, 95447, Bayreuth, Germany.
authors.forename: Jürgen
authors.identifier: http://orcid.org/0000-0002-7278-7952
authors.initials: J
authors.lastname: Senker
keywords: NMR crystallography; NMR spectroscopy; electron diffraction; poly(triazine imide); structure elucidation