Climbing end image algorithm to locate transition states

A climbing end image algorithm is proposed to locate transition state structures based on the nudged elastic band method. According to this algorithm, all intermediate structures, known as images in the nudged-elastic-band method, can climb the potential energy surface along the reaction path to the transition state. The number of images can be reduced because all images are located in the limited transition state region. This method was applied to the simplified Wittig reaction, and two transition state structures were successfully found with high reliability.