:term:`FULL_HESS_EVERY ` """"""""""""""""""""""""""""""""""""""""""""""""""" Frequency with which to compute the full Hessian in the course of a geometry optimization. 0 means to compute the initial Hessian only, 1 means recompute every step, and N means recompute every N steps. The default (-1) is to never compute the full Hessian. * **Type**: integer * **Default**: -1