Sterically Controlled Solid-State Mechanochemistry Under Hydrostatic Pressure

ORAL

Abstract

Mechanical stress can modify the energy landscape of chemical reactions and enable new reaction pathways. Mechanochemical mechanisms under tensile stress have been extensively studied in one-dimensional polymers. However, bond activation has not been possible with hydrostatic pressure in three-dimensional solids. Here we show that mechanochemistry through isotropic compression is possible by molecularly engineering structures that translate macroscopic isotropic stress into molecular-level anisotropic strain. We engineer molecules with mechanically heterogeneous components consisting of a compressible mechanophore and incompressible ligands. In these ‘molecular anvils’, isotropic stress leads to anisotropic deformation of the compressible mechanophore and activating bonds. We combine experiments and computations to demonstrate hydrostatic-pressure-driven redox reactions in crystalline metal-organic chalcogenides, where bending of bond angles or shearing of adjacent chains activates the metal-chalcogen bonds. These results reveal an unexplored mechanism and enable new possibilities for high-specificity mechanosynthesis.

–

Presenters

  • Hao Yan

    Stanford University

Authors

  • Hao Yan

    Stanford University

  • Giulia Galli

    Institute for Molecular Engineering, University of Chicago, Institute for Molecular Engineering and Materials Science Division, University of Chicago and Argonne National Laboratory, University of Chicago, Argonne National Lab, Institute for Molecular Engineering and Department of Chemistry, University of Chicago, University of Chicago and Argonne National Laboratory, The Institute for Molecular Engineering, University of Chicago, University of Chicago, Institute for Molecular Engineering, Univ. of Chicago; Department of Chemistry, Univ. of Chicago; Materials Science Division, Argonne National Laboratory

  • Wendy Mao

    Stanford University

  • Nicholas A Melosh

    Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Materials Science and Engineering, Stanford University

  • Zhixun Shen

    Stanford University, SLAC National Accelerator Laboratory, SIMES, SLAC National Accelerator Lab, GLAM, Stanford University, Applied physics, Stanford University, Department of Applied Physics, Stanford University