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Thanks to their high initial electrochemical properties and broad compositional flexibility, lithium-rich disordered rocksalt cathode-active materials including high-performance manganese-only materials appear as a potential replacement to the cobalt-based current market leader “NMC” material. The main issue with these materials is their lack of stability. However, recent works have identified bulk fluorination as a potential solution to stabilize these compounds. There is, however, a clear lack of diversity in fluorination agents used to synthesize these disordered rocksalts, as most publications used LiF, a very stable compound. To achieve manganese-only materials, manganese oxyfluorides represent promising precursors, but the literature reports only MnO3F and Mn2O2F9, which are both unstable and hazardous. The present study develops several strategies for synthesis and a tailored characterization methodology to explore the chemical space of direct fluorination of manganese oxide MnO with molecular fluorine and shows how to tune its reactivity to achieve a range of novel, safe, and finely tunable manganese oxyfluorides of general formula MnOFx, with xgoing from 0 to 1 synthesized via a fluorine insertion mechanism.

Abstract. Reaction of commercially available tetraethylene glycol with different alkaline earth metal halides affords tetraethylene glycol complexes with different coordination numbers at the metal ion and structural features; depending on the ionic radius of the metal ion, one or two ligand molecules will be coordinated to the metal ion. In this article we will first present complexes with Mg2+([Mg(C8H18O5)(H2O)2]Cl·I) (1), Ca2+([Ca(C8H18O5)·3H2O]Cl2(2), [Ca(C8H18O5)(H2O)2]I2(3), [Ca(C8H18O5)(H2O)3]I2·H2O (4), ([Ca(C8H18O5)(H2O)3]Cl·I) (5),Sr2+([Sr(C8H18O5)(H2O)4]Cl2(6), [Sr(C8H18O5)2]I2·CHCl3) (7) and Ba2+([Ba(C8H18O5)2]I2) (8). Secondly we will show preliminary tests for the combustion of some selected compounds and their thermal decomposition behavior. Furthermore, selected compounds were evaporated by MOCVD (metal organic chemical vapor deposition) to evaluate their capacity as future single source precursors for oxide materials.

Single crystals of Cu(C6H4NO2)(C6H5NO2)(H2O)2[Mo2O6]n were grown hydrothermally and characterized by X-ray diffraction and elemental analysis. This compound shows a new 18{Mo2O8}4-infinite polymer chain, which is connected via copper(I) nicotinate subunits, forming an overall 3D network