I am currently using Q-Chem 5.4 in order to calculate MECI using SP-TDDFT. I have checked that the criterion that is used to converge a calculation is based on the gradient, energy change and atomic displacement. I have been doing it for many small molecules and in many cases what has happened to me is that the calculation is converged in terms of displacement and gradient but not in energy. Even in that case, it is considered by the program to be converged, as shown below:

```
Maximum Tolerance Cnvgd?
Gradient 0.000204 0.000300 YES
Displacement 0.000277 0.001200 YES
Energy change -0.000184 0.000001 NO
```

Final energy is -499.68276174754624

** OPTIMIZATION CONVERGED **

These are the keywords and instructions of my input:

$rem

JOBTYPE = opt

MECP_OPT = true

SPIN_FLIP = true

MECP_METHODS = mecp_direct

GEOM_OPT_MAX_CYCLES = 1200

CIS_N_ROOTS = 5

MECP_STATE1 = [0,1] ! Looking for state of charge 0, 1st singlet ie/ the GS !

MECP_STATE2 = [0,2] ! Second singlet

METHOD = PBE0

BASIS = 6-31+G*

SCF_CONVERGENCE = 9

SYM_IGNORE = true

$end

**Is there anyway of making the calculation converge also in terms of energy?**

Thank you