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lello
raffaele.borrelli@unito.it

I was running a geometry optimization at MCSCF level followed by a frequency calculation. The numerical Hessian calculation took too long
for the queue and now I have to restart it.

The problem is that after NSERCH=0 in the PUNCH file I can only find
the occupied MCSCF orbitals, virtual orbitals are missing
(ie the $VEC field contains only the first 80 occupied orbitals,
not all the 348 that I was expecting).
I have restarted the job by using the optimized geometry using as
a guess only the occupied natural orbitals found in the PUNCH file,
however, the MCSCF procedure converged to a slightly different
energy (10^-5 hartree above the original energy).

My first question is: how can I make MCSCF punch all the files
for each geometry optimization step?

Second, I am not sure the energy is accurate enough to restart the
frequency calculation. Indeed the error of 10^-5 hartree is of the
same order of the energy differences of the numerical differentiation
scheme. Anyone has any suggestion on how to
improve the restart of the frequency calculation?


Thanks,
Lello