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  1. Free, publicly-accessible full text available October 5, 2023
  2. Free, publicly-accessible full text available September 1, 2023
  3. Abstract

    Modifiers are commonly used in natural, biological, and synthetic crystallization to tailor the growth of diverse materials. Here, we identify tautomers as a new class of modifiers where the dynamic interconversion between solute and its corresponding tautomer(s) produces native crystal growth inhibitors. The macroscopic and microscopic effects imposed by inhibitor-crystal interactions reveal dual mechanisms of inhibition where tautomer occlusion within crystals that leads to natural bending, tunes elastic modulus, and selectively alters the rate of crystal dissolution. Our study focuses on ammonium urate crystallization and shows that the keto-enol form of urate, which exists as a minor tautomer, is a potent inhibitor that nearly suppresses crystal growth at select solution alkalinity and supersaturation. The generalizability of this phenomenon is demonstrated for two additional tautomers with relevance to biological systems and pharmaceuticals. These findings offer potential routes in crystal engineering to strategically control the mechanical or physicochemical properties of tautomeric materials.

  4. Free, publicly-accessible full text available April 15, 2023
  5. Free, publicly-accessible full text available June 1, 2023
  6. Free, publicly-accessible full text available April 13, 2023
  7. CuZrO 3 has been hypothesized to be a catalytic material with potential applications for CO 2 reduction. Unfortunately, this material has received limited attention in the literature, and to the best of our knowledge the exact crystal structure is still unknown. To address this challenge, we utilize several different structural prediction techniques in concert, including the Universal Structure Predictor: Evolutionary Xtallography (USPEX), the Materials Project Structure Predictor, and the Open Quantum Materials Database (OQMD). Leveraging these structural prediction techniques in conjunction with Density-Functional Theory (DFT) calculations, we determine a possible structure for CuZrO 3 , which resembles a “sandwich” morphology. Our calculations reveal that this new structure is significantly lower in energy than a previously hypothesized perovskite structure, albeit it still has a thermodynamic preference to decompose into CuO and ZrO 2 . In addition, we experimentally tried to synthesize CuZrO 3 based on literature reports and compared computational to experimental X-ray Diffraction (XRD) patterns confirming that the final product is a mixture of CuO and ZrO 2 . Finally, we conducted a computational surface energetics and CO 2 adsorption study on our discovered sandwich morphology, demonstrating that CO 2 can adsorb and activate on the material. However, these COmore »2 adsorption results deviate from previously reported results further confirming that the CuZrO 3 is a metastable form and may not be experimentally accessible as a well-mixed oxide, since phase segregation to CuO and ZrO 2 is preferred. Taken together, our combined computational and experimental study provides evidence that the synthesis of CuZrO 3 is extremely difficult and if this oxide exists, it should have a sandwich-like morphology.« less
  8. Free, publicly-accessible full text available October 25, 2023