The dimer method was used to search for possible transition states of interstitials and small interstitial clusters in SiC. The method used only the first derivatives of the potential energy in order to find saddle points without knowing the final state of the transition. The possible migration pathway for the C interstitial was found to consist of a first-nearest neighbor jump via a Si site or second-nearest neighbor jump; but the relative probability of the second-nearest neighbor jump was very low.

Finding Possible Transition States of Defects in Silicon Carbide and Alpha-Iron using the Dimer Method. F.Gao, G.Henkelman, W.J.Weber, L.R.Corrales, H.Jónsson: Nuclear Instruments and Methods in Physics Research Section B, 2003, 202, 1-7