Wolfgang Quapp  and Josep Maria Bofill

A Contribution to a Theory of Mechanochemical Pathways by means of
Newton Trajectories



1) Leipzig University, Mathematisches Institut, Universit"at Leipzig,
PF 100920, D-04009 Leipzig, Germany 
quapp@uni-leipzig.de

2) Departament de Qu'imica Org`anica, Universitat de Barcelona,
and 
Institut de Qu'imica Te`orica i Computacional, Universitat
de Barcelona, (IQTCUB), Mart'i i Franqu`es, 1, 08028 Barcelona, Spain
jmbofill@ub.net


Received: February 10, 2016 , Revised: Mart 22  , Accepted:

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keywords:
 Effective potential energy surface, Mechanochemistry, Newton trajectory,
Barrier breakdown, Saddle, Intermediate, Reaction Path

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The reaction path is a central subject in theoretical chemistry.
It is a pathway imagined on the potential energy surface (PES). It provides
a one-dimensional description of a chemical reaction in an N-dimensional
configuration space.
Additionally, one can apply mechanical stress in a defined direction to the
molecule and generate an effective PES. Changes for minima and saddle points 
by the stress are described by Newton trajectories on the original PES.
The barrier of a reaction fully breaks down for the maximal value of the
norm of the gradient of the PES alon a pulling Newton trajectory. This 
point is named barrier breakdown point (BBP).
We discuss topologically different, 2-dimensional examples for this model
to understand and classify the mechanochemistry of molecules.