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Abstract A series of Co^2+/3+and Fe^2+/3+complexes is prepared using three variants of a hexadentate tris(imidazole)triazacyclononane ligand bearing different 4‐alkyl substituents on the imidazole rings. The steric bulk of the alkyl substituent (R=H,ⁱPr, or^tBu) alters the preferred size of the ligand binding cavity by inhibiting close approach of the imidazole donors with bulky substituents. The resulting changes in geometry, redox potentials, spin states, and optical properties are catalogued across the series, demonstrating redox potential tuning over at least 670 mV as well as spin state switching based on the choice of substituent. The ligand field splitting of the complexes decreases with increasing bulk of the substituents. Tuning of the steric bulk of the substituents in these positions therefore allows for the electronic properties of the complexes to be fine‐tuned in a manner orthogonal to the donor properties of the substituents. 

Alloyed Ba(Zr_1−xTi_x)S₃nanoparticles are preparedviaa solution-phase route. The phase evolution from a chalcogenide perovskite phase at lowxto a hexagonal non-perovskite phase at highxis tracked along with changes in the optical properties. 

The versatility of early transition metal chalcogenide nanomaterials, including chalcogenide perovskites, has attracted enormous attention for a variety of applications, such as photovoltaics, photocatalysis, and optoelectronic devices. These nanomaterials exhibit unique electronic and optical properties, allowing for a broad range of applications, depending on their chemical composition and crystal structure. However, solution-phase synthesis of early transition metal chalcogenide nanocrystals is challenging due, in part, to their high crystallization energy and oxophilicity. In this feature article, we explore various synthetic routes reported for inorganic ternary and binary sulfide and selenide nanomaterials that include transition metals from groups 3, 4, and 5. By systematically comparing different synthetic approaches, we identify trends and insights into the chemistry of these chalcogenide nanomaterials. 

Chalcogenide perovskites such as BaZrS 3 have promising optoelectronic properties. Methods to produce these materials at low temperatures, especially in the solution phase, are currently scarce. We describe a solution-phase synthesis of colloidal nanoparticles of BaZrS 3 using reactive metal amide precursors. The nanomaterials are crystallographically and spectroscopically characterized. 

The synthesis and structures of N , N -dialkyldithiocarbamate complexes of barium are reported; the compounds crystallize as one-dimensional coordination polymers. In combination with a titanium dithiocarbamate precursor, the compounds are demonstrated as competent single-source precursors for the solution-based preparation of colloidal BaTiS 3 nanorods.