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Mechanical force drives distinct chemical reactions; yet, its vectoral nature results in complicated coupling with reaction trajectories. Here, we utilize a physical organic model inspired by the classical Morse potential and its differential forms to identify effective force constant (keff) and reaction energy (ΔE) as key molecular features that govern mechanochemical kinetics. Through a comprehensive experimental and computational investigation with four norborn-2-en-7-one (NEO) mechanophores, we establish the relationship between these features and the force-dependent energetic changes along the reaction pathways. We show that the complex kinetic behavior of the tensioned bonds is generally and quantitatively predicted by a simple multivariate linear regression based on the two easily computed features with a straightforward workflow. These results demonstrate a general mechanistic framework for mechanochemical reactions under tensile force and provide a highly accessible tool for the large-scale computational screening in the design of mechanophores.
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A systematic workflow for mechanophore design
Advancing mechanoresponsive materials require novel mechanophores, though clear and structured design guidelines are still emerging. In this work, we present a systematic workflow aimed at facilitating the design and discovery of new mechanophores. By integrating the classic iso-metrical CoGEF approach with our innovative iso-tensional Tension Model of Bond Activation (TMBA) simulation, the workflow described herein enables comprehensive evaluation of mechanophore candidates prior to experimental implementation, with a practical case study included for detailed illustration. This predictive capability allows computational screening, efficient identification and filtering away unexpected issues while providing valuable insights for potential structural optimization.
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- Award ID(s):
- 2116298
- PAR ID:
- 10649190
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- MRS Communications
- Volume:
- 15
- Issue:
- 5
- ISSN:
- 2159-6867
- Page Range / eLocation ID:
- 1030 to 1039
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1557/s43579-025-00827-5
