Mechanism of the effect of mechanical deformations on the ionization potential of polyethylene

In addition to an increase in the solvation energy of the charged particles in volume compression, which has a value of less than 1 eV according to their estimation and does not permit explaining the effects observed, there is only one way of surmounting the higher energy barrier which prevents ionization in a polymer: a decrease in the IP of the molecule itself, i.e., IP/sub g/, due to its deformation. Experimental verification of this hypothesis is difficult, and they thus resorted to calculation methods in quantum chemistry to establish the dependence of the IP of a molecule on the strain energy. The MNDO method was used. The calculations were performed for molecules of methane and propane, which can be considered the simplest compounds which model polyethylene