Controlling Electron Delocalization in Vanadium-Based Hybrid Bronzes through Molecular Templation.

We show that the conductivity of hybrid vanadium bronzes-mixed-valence organic-inorganic vanadium oxides-can be tuned over six orders of magnitude through judicious choice of molecular component. By systematically varying the steric profile, charge density, and propensity to hydrogen bond across a series of eight diammonium-based molecules, we engender multiple distinct motifs of V-O connectivity within the two-dimensional vanadium oxide layers of a family of bulk crystalline hybrid materials. A combination of single-crystal and powder X-ray diffraction analysis, variable-temperature electrical transport measurements, and a range of spectroscopic methods, including UV/Visible diffuse reflectance, X-ray photoelectron, and electron paramagnetic resonance are employed to probe how vanadium oxide layer topology correlates with electron localization.

Rare earth arylsilazido compounds with inequivalent secondary interactions.

A new bulky silazido ligand, -N(SiHMe2)Dipp (Dipp = C6H3-2,6-iPr2), supports planar, three-coordinate homoleptic rare earth complexes Ln{N(SiHMe2)Dipp}3 (Ln = Sc, Y, and Lu), each containing three secondary Ln↼HSi interactions and one agostic CH bond. Y{N(SiHMe2)Dipp}3 and acetophenone react via hydrosilylation, rather than by insertion into the Y-N bond or by enolate formation.