Processing involving mechanical treatment in order to achieve chemical reactions.

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Chemistry accomplished by mechanical systems directly controlling the reactant molecules; the formation or breaking of chemical bonds under direct mechanical control.� [See How does 'mechanochemistry' work?]

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In this volume, the chemistry of processes in which mechanical systems operating with atomic-scale precision either guide, drive, or are driven by chemical transformations. In general usage, the chemistry of processes in which energy is converted from mechanical to chemical form, or vice versa.

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The direct, mechanical control of molecular structure formation and manipulation to form atomically precise products [K. Eric Drexler. From Nanosystems: Molecular Machinery, Manufacturing, and Computation]

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