Mixed-Metal Alloying in Hybrid Bronzes.

We show that substitutional alloying during the aqueous self-assembly of layered organic-templated metal oxides produces single-phase mixed-metal hybrids. Single-crystal X-ray diffraction, bulk elemental analyses, and vibrational and electronic spectroscopies corroborate a solid solution of Mo and W atoms at lattice sites within the two-dimensional metal oxide layers. Mild postsynthetic reduction then introduces relatively delocalized electrons to afford mixed-metal hybrid bronzes.

Hybrid bronzes: mixed-valence organic-inorganic metal oxides as a tunable material platform.

We demonstrate that mixed-valence layered organic-inorganic metal oxides of the form (L)HMO (L = neutral ligand; M = Mo, W; = 0.5, 1; 0 < < 2), which we call , can be readily synthesized through mild solution-state self-assembly reactions to integrate the stability and electronic utility of inorganic metal oxide bronzes with the chemical diversity and functionality of organic molecules. We use single-crystal and powder X-ray diffraction coupled with X-ray, electronic, and vibrational spectroscopies to show that the products of aqueous pre-, mid-, or post-synthetic reduction are mixed-valence versions of highly crystalline layered hybrid oxides.

Calculation of and Its Use as a Descriptor for the Theoretical Calculation of pa Values for Carboxylic Acids.

The theoretical calculation of pa values for Brønsted acids is a challenging task that involves sophisticated and time-consuming methods. Therefore, heuristic approaches are efficient and appealing methodologies to approximate these values. Herein, we used the maximum surface electrostatic potential () on the acidic hydrogen atoms of carboxylic acids to describe the H-bond interaction with water (the same descriptor that is used to characterize σ-bonded complexes) and correlate the results with experimental pa values to obtain a predictive model for other carboxylic acids.