[molpro-user] multi input processing in version 2010.1
werner at theochem.uni-stuttgart.de
Thu Dec 1 10:53:34 GMT 2011
I now implemented a "FORCEINP" option in multi, which forces that all input
is processed also during geometry optimizations and frequency calculations. Normally
input is skipped during OPTG/FREQ calculations, and the program uses automatically the
appropriate starting orbitals, occupations etc. Using the FORCEINP option is not recommended
and at your own risk (just use multi,forceinp;...).
If the program does not converge with neighboring orbitals in optimizations or reaction path
calculations, this is most likely due to root flipping or changes of the character of some
active/inactive orbital along the path. So it is better to look first for the physical reason of the
problem than to fiddle with different starting orbitals.
The stepsize in reaction path calculations can be affected by the STEPMAX option (default is 0.3).
The value if idir (direction) only affects the initial step. I will update the documentation
to clarify this point.
The patch containing FORCEINP is currently being checked on various platforms and should appear
soon on the server.
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