Nudged elastic stiffness band method: A method to solve kinks problems of reaction paths

The nudged elastic band (NEB) method has been widely employed for reaction path (RP) finding; however, certain NEB calculations do not converge to the minimum energy paths (MEPs) because of the occurrence of kinks, which are caused by the free bending of bands. Thus, we propose an extension of the NEB method, called the nudged elastic stiffness band (NESB) method, which adds the stress of stiffness using a beam theory. Here we present results from three examples: the NFK potential, the RPs of the Witting reaction, and finding saddle points for a set of five chemical reaction benchmarks. The results showed that the NESB method has three advantages: to decrease the number of iterations, shrink the length of the pathways from reducing unnecessary fluctuations, and find TS structures by converging to paths close to the MEPs for systems that have sharp curves on the MEPs.

Automated summary

The nudged elastic band (NEB) method is widely used for reaction path (RP) finding, but some NEB calculations fail to converge to the minimum energy paths (MEPs) due to the occurrence of kinks caused by free bending of the bands. Therefore, we propose an extension of the NEB method called the nudged elastic stiffness band (NESB) method, which incorporates stiffness stress using a beam theory. The results from three examples demonstrate that the NESB method has three advantages: reducing the number of iterations, shortening the pathway length by reducing unnecessary fluctuations, and finding transition state (TS) structures by converging to paths close to the MEPs for systems with sharp curves on the MEPs.