-Fast inertial relaxation engine (FIRE) -Polak-Ribière conjugate gradient (CG) -Limited-memory Broyen-Fletcher-Goldfarb-Shanno (L-BFGS) -Steepest descents (SD) -Quick-Min (QM) (iv) Vibration analysis The implementation is available as of Amsterdam Modeling Suite 2018 and later . Theoretical background information and instructions on how to use the transition state tools within the ReaxFF implementation are given in the SI.