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Solving the Hydrogen and Lithium Substructure of Poly(triazine imide)/LiCl Using NMR Crystallography
Author(s) -
Mesch Maria B.,
Bärwinkel Kilian,
Krysiak Yaşar,
Martineau Charlotte,
Taulelle Francis,
Neder Reinhard B.,
Kolb Ute,
Senker Jürgen
Publication year - 2016
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201603726
Subject(s) - substructure , imide , triazine , chemistry , lithium (medication) , crystallography , ion , lithium chloride , materials science , inorganic chemistry , polymer chemistry , organic chemistry , medicine , structural engineering , engineering , endocrinology
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 P 2 1 2 1 2 1 . In this way, we demonstrate that, in particular, the above‐mentioned techniques allow for smart interplay in delineating the real structure of PTI/LiCl.