### 46.1.3 Options to modify convergence criteria

The standard MOLPRO convergency criterion requires the maximum component of the gradient to be less then [a.u.] and the maximum energy change to be less than [H] or the maximum component of the gradient to be less then [a.u.] and the maximum component of the step to be less then [a.u.].

It is also possible to use the convergency criterion of the Gaussian program package. It is somewhat weaker than the MOLPRO criterion and requires the maximum component of the gradient to be less then [a.u.] and the root mean square (RMS) of the gradient to be less then [a.u.] as well as the maximum component of the optimization step to be less then [a.u.] and the RMS of the optimization step to be less then [a.u.].

MAXIT=maxit
maximum number of optimization cycles. The default is 50.
required accuracy of the optimized gradient. The default is .
ENERGY=threnerg
required accuracy of the optimized energy. The default is .
STEP=thrstep
convergence threshold for the geometry optimization step. The default is .
BAKER
(logical). Use Baker's convergency criteria (see J. Baker, J. Comp. Chem. 14,1085 (1993)).
GAUSSIAN
(logical). Use Gaussian convergency criteria.
SRMS=thrsrms
sets (for Gaussian convergency criterion) the required accuracy of the RMS of the optimization step. The default is .
GRMS=thrgrms
sets (for Gaussian convergency criterion) the required accuracy of the RMS of the gradient. The default is .
FREEZE=thrfreez
Freeze DFT grid and domains in local calculations if the step length is smaller than thrfreez (default 0.01).

Note: The defaults for the convergence parameters can also be changed by using a global GTHRESH directive, i.e.