COnstraint GEometry to simulate Forces

COGEF is an ASE module which contains tools for simulating force-induced bond-breaking reactions based on the COnstrained Geometries simulate External Force (COGEF) method (Beyer, M. K. J. Chem. Phys. 2000, 112, 7307).

This module can be used to answer the question: How much force is needed to break a bond in a molecule? In a first step the maximum force can be obtained from the maximum slope of the energy-extension curve when the end-to-end distance of the molecule is stretched. In further steps, more precise rupture forces in dependence of the loading rate can be obtained by including the effects of temperature, a two-dimensional investigation of the energy landscape, multiple transitions into broken molecule forms and back reactions from the broken into the intact form. Furthermore polymer effects and the spring effect of a cantilever can be included to simulate force-extension curves from atomic force microscopy experiments with constant pulling velocity.