"The NEB and min-mode following (dimer/Lanczos) saddle point finding methods use a force projection in order to direct the optimizers towards minimum energy paths and saddle points. These modifications to the force mean that the energy is no longer consistent with the force being optimized. Because of this, we can only use optimizers that are solely based upon the force (and not the energy). The quasi-Newton and quick-min (IBRION=1 and 3 respectively) optimizers that are built into VASP are both force-based, but the conjugate-gradient method (IBRION=2) is not"官网的说明,只能用IBRION=1或3来做NEB,因为NEB需要力和能量不会同步优化(同时最小化)。