Improved Elastic Image Pair Method for Finding Transition States.

The elastic image pair (EIP) method is a robust method for finding approximate transition states between two local minima. However, the original implementation of the method had some limitations. In this work, we present an improved EIP method, in which the moving procedure of the image pair and the convergence strategy are modified. In addition, this method is combined with the rational function optimization method to give exact transition states. Tests on a set of 45 different reactions show the reliability and efficiency in finding transition states.