title: Reaction rates in a theory of mechanochemical pathways.
abstract: If one applies mechanical stress to a molecule in a defined direction then one generates a new, effective potential energy surface (PES). Changes for minima and saddle points (SP) by the stress are described by Newton trajectories on the original PES (Quapp and Bofill, Theor. Chem. Acc. 2016, 135, 113). The barrier of a reaction fully breaks down for the maximal value of the norm of the gradient of the PES along a pulling Newton trajectory. This point is named barrier breakdown point (BBP). Depending on the pulling direction, different reaction pathways can be enforced. If the exit SP of the chosen pulling direction is not the lowest SP of the reactant valley, on the original PES, then the SPs must change their role anywhere: in this case the curve of the log(rate) over the pulling force of a forward reaction can show a deviation from the normal concave curvature. We discuss simple, two-dimensional examples for this model to understand more deeply the mechanochemistry of molecular systems under a mechanical stress. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Mathematics, University Leipzig, PF 100920, Leipzig, D-04009, Germany. quapp@uni-leipzig.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Quapp
authors.affiliation: Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Universitat de Barcelona; and Institut de Química Teòrica i Computacional, Universitat de Barcelona, (IQTCUB), Martí i Franquès, 1, Barcelona, 08028, Spain.
authors.forename: Josep Maria
authors.initials: JM
authors.lastname: Bofill
keywords: Newton trajectory; barrier breakdown; effective potential energy surface; intermediate; mechanochemistry; reaction rate; saddle