Correlated Anion Disorder in Heteroanionic Cubic TiOF 2
Year: 2024
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Resolving anion configurations in heteroanionic materials is crucial for understanding and controlling their properties. For anion-disordered oxyfluorides, conventional Bragg diffraction cannot fully resolve the anionic structure, necessitating alternative structure determination methods. We have investigated the anionic structure of anion-disordered cubic (ReO 3 -type) TiOF 2 using X-ray pair distribution function (PDF), 19 F MAS NMR analysis, density functional theory (DFT), cluster expansion modeling, and genetic-algorithm structure prediction. Our computational data predict short-range anion ordering in TiOF 2, characterized by predominant cis -[O 2 F 4 ] titanium coordination, resulting in correlated anion disorder at longer ranges. To validate our predictions, we generated partially disordered supercells using genetic-algorithm structure prediction and computed simulated X-ray PDF data and 19 F MAS NMR spectra, which we compared directly to experimental data. To construct our simulated 19 F NMR spectra, we derived new transformation functions for mapping calculated magnetic shieldings to predicted magnetic chemical shifts in titanium (oxy)fluorides, obtained by fitting DFT-calculated magnetic shieldings to previously published experimental chemical shift data for TiF 4 . We find good agreement between our simulated and experimental data, which supports our computationally predicted structural model and demonstrates the effectiveness of complementary experimental and computational techniques in resolving anionic structure in anion-disordered oxyfluorides. From additional DFT calculations, we predict that increasing anion disorder makes lithium intercalation more favorable by, on average, up to 2 eV, highlighting the significant effect of variations in short-range order on the intercalation properties of anion-disordered materials.
DOI: 10.1021/jacs.4c06304
Institutions: Centre National de la Recherche Scientifique, Le Mans Université, Institut des Molécules et Matériaux du Mans, The Faraday Institution, University of Bath, University of Birmingham, Sorbonne Université, Réseau sur le Stockage Electrochimique de l'énergie, PHENIX laboratory, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, CEA Paris-Saclay - Etablissement de Saclay, CEA Paris-Saclay, Argonne National Laboratory, Advanced Photon Source
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Funders: U.S. Department of Energy, Faraday Institution, Le Mans Université, Royal Society, University of Bath, Centre National de la Recherche Scientifique, Université Paris-Saclay, Grand Équipement National De Calcul Intensif, Conseil Régional des Pays de la Loire, Sorbonne Université, Office of Science, Engineering and Physical Sciences Research Council, Argonne National Laboratory
Awards: G102163711, G107546177, G1313983767, G1664757510, G1673663507, G2287611682, G2415135322, G262962599, G3075337988, G3510705891, G417250887, G4678694819, G498139845, G5019177369, G5904151224, G6848031779, G6918803902, Tier 2 Hub in Materials and Molecular Modelling, G8429489860, G969889393, G993149817
OpenAlex ID: W4401033122